Five morphological character complexes are surveyed as a primary basis for the consideration of lower teleostean relationships.The first two of these-the caudal skeleton and the connection between the swim bladder and the ear-are reviewed from the literature.The accounts of the other three are based on an examination of modern lower teleosts.The main results from these three complexes are as follows:
(1) The postcleithrum of osteoglossiform fishes is the single anocleithrum inherited from ancestral forms.Other modern teleosts may have two additional postcleithra which seem to be scale derivatives.The iniomous (myctophiform) genus Aulopus appears to have three postcleithra, as do various modern lower teleosts, but more advanced forms have a maximum of two.
(2) In the evolution of structures associated with pectoral fin movements two major series of changes seem to have occurred.One of these has to do with the anteriormost pectoral ray and differentiates modern lower teleosts from their “holostean”ancestors.The other is a series of individually minor changes associated with the loss of the meso-coracoid arch in the iniomous fishes and higher teleosts.
(3) Of the various types of premaxillary movements that have evolved in lower teleosts, two have led to widely adopted protrusion systems.The acanthopterygian system of most higher teleosts, represented in an incipient stage in the iniomous genus Aulopus, provides a firm bite against protruded premaxillaries.A primary component seems to be the strong palatine strut that extends over a proximal part of the maxillary, with exclusion of the maxillary from the gape a secondary but almost constant feature.The second highly successful protrusion system, that of the cyprinoid ostariophysines, seems to have evolved in association with a suction system of feeding.A key element in the development of the cyprinoid system appears to be the downward and forward pull on the distal end of the premaxillary caused by a lip-like structure around the corner of the mouth.
With regard to interrelationships the conclusions reached are as follows.The elopiform, salmoniform, clupeiform, gonorynchiform, and ostariophysine fishes form a series of related groups that are clearly delimited from the osteoglossiform fishes on one side and from the iniomous-acanthopterygian teleosts on the other.The elopiform fishes represent an early offshoot from this central lower teleostean stock.The clupeiform, gonorynchiform, and ostariophysine fishes, like the iniomous-acanthopterygian series, all seem to have evolved in different ways from a basal type of lower teleost which is here considered to be salmoniform.Among these salmoniform derivatives, the gonorynchiform and ostariophysine series seem to be closest to one another.

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A classification of actinopterygian intestinal patterns represented by 596 species is presented.Individual and developmental variations, distribution, and interrelationships of intestinal patterns were studied.The low conspecific variation, non-random pattern variation in groups with complex patterns, and resemblance of intestinal patterns among mem-bers of monophyletic groups suggest that intestinal pattern provides valuable information regarding phylogenetic interrelationships.

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Four nominal species in the genus Lepidion of the family Moridae from the north-western Pacific were reviewed taxonomically.Two of them, L.inosimae and L.schmidti, were found to be distinct species. L.oidema is a synonym of L.inosimae, and L.modestus is excluded from the genus.

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A new species of the Zoarcidae, Lycodes sadoensis, is described from the Sea of Japan.It resembles L.teraoi in proportional measurements and counts.However, it is separable from L.teraoi in having blotches on the body.

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Tosanoides flavofasciatus is described as a new species in the family Serranidae, subfamily Anthiinae.This new fish was found in Sagami Bay and the Tonga Ridge.It is the second species of the genus Tosanoides and closely related to T.filamentosus Kamohara, from which it differs in having a short first dorsal spine and short filamentous pelvic fin rays, as well as in coloration.

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The vitelline syncytium of the embryonic rockfish, Sebastes schlegeli, was examined by electron microscopy.The syncytium encloses the entire yolk mass in the yolksac, separating it from the embryonic body and the circulating fetal blood.Numerous small yolk droplets fused into coagulated masses were detected in the syncytial cytoplasm near the border with the yolk mass.Two structurally different regions were distinguished in the syncytium: one characterized by an extensive network of the smooth surfaced endoplasmic reticulum, numerous mitochondria and a large number of glycogen granules, and the other by compactly arranged cisternae of the rough surfaced endoplasmic reticulum and developed Golgi complexes.In some surface areas where the endothelial wall of blood vessels is incomplete and the fetal blood is in direct contact, the syncytium showed finely vacuolated cytoplasm forming an intricate structure between the cytoplasmic processes of the blood cells.These characteristic features of the vitelline syncytium are discussed in view of its functional significance in yolk absorption.

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The present report deals with age and growth estimations based on ring marks on scales for Parapristipoma trilineatum (Pomadasyidae).Materials used in this study consist of 1170 individuals ranging from 49 to 355.7 mm in fork length.They were taken by set net, hook and line and gill net from coastal areas of Kumano-nada during the period from March, 1978 to April, 1979.A number of scales were taken from a row beneath the lateral line of the left side of the fish just posterior to the tip of the pectoral fin, and a scale of regular shape among them was selected and used for measurement.
The results obtained are summarized as follows:
1) The relationships between the fork length (L in mm) and total length (TL in mm), standard length (SL in mm) and body weight (W in g) were shown by the following equations:
logTL=1.01logL+0.019
logSL=1.02logL-0.106
logW=3.25logL-5.388
2) Ring marks on scales were formed twice in a year, both in summer and in winter.Of these two ring marks, the ring mark formed in the period from January to February was used for the estimation of age and growth of the fish.The other ring was considered to be the spawning mark, because the ring mark was inconspicuous in immature specimens and the time of ring formation in mature specimens corresponded to the spawning season from June to July.
3) An anti-Lee phenomenon was observed in the mean value of each ring radius.-Phenomenon may be attributable to the growth of old tissue of scale.
4) The relationship between the fork length and scale radius (R in mm) was shown by the equation log L=0.881 log R+1.842.The fork lengths at the time of ring formation were calculated using the above equation.
5) The results obtained from the Walford's growth transformation method indicated that the plots of l_n+1 against l_n fall on a straight line, given by the equation l_n+i= 0.779l_n+78.3.
6) Since the time difference between spawning and ring formation on scales was about 0.5 year, the Bertalanffy's growth equation for full age (t) in fork length (L_t) and weight (W_t) was given as follows:
L_t=355 (1-e^{-0.249 (t+0.731)} )
W_t=794 (1-e^{-0.249 (t+0.731)} ) ^3.25
7) There was no sex-associated difference in growth.

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The effect of light on leucophores of an isolated scale from the wild-type medaka Oryzias latipes was investigated.Leucophores were directly exposed beneath a light source of 150 or 300 lux.Fully dispersed leucophores in a M/7.5 KC1 solution and fully aggregated leucophores in a physiological saline solution did not show any noticeable response under illumination except for a very active Brownian movement of leucosomes.On the other hand, leucophores aggregated under the effects of both a stimulant and an inhibitor of the adrenergic β-receptor, dispersed under illumination and this response was found to be reversible.From the above findings, it was concluded that light directly induces leucosome dispersion in leucophores without any mediation of the adrenergic β-receptor.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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A mature female of the bramid fish, Taract-clnhrs longipinnis(Lowe)was caught by tuna long line from the T.V.Nagasaki-maru, Nagasaki University, at around 9°31'S, 118°50'E in the eastern Indian Ocean on August 8, 1966.The fish was 78 cm TL, 61 cm SL, about 10 kg BW, and the viscera weight was about 1.5 kg.The abdomen of the fish was scarcely swollen, but mature translucent eggs of a light yellow tint were squeezed from the fish.The eggs were spherical in shape and separately pelagic in the sea water at a temperature of about 26°C and a salinity of about 34.5‰.The eggs preserved in 5%formalin are 1.2mm in diameter with a conspicuous perivitelline space, a homogeneous 0.9 mm yolk, and a 0.3 mm oil globule.
The mature ovaries of the fish were small and about 90 g in weight, and the GSI was less than I.The ovaries contained about seventy thousand mature eggs.
It was considered that the mature female fish was hooked at a depth of 80-150 m.The ocea-nographic observation data suggest that the fish was living in the mid-layer of the ocean at tem-peratures of 11.10-.25.84°C and at salinities of 34.54-34.76‰.

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