1. The present study deals with the role of the rectal bladder of spiders in the water conservation. 2. In the experiments, adult females of the following species were used: Araneus ventricosus (L. KOCH), Nephila clavata L. KOCH and Agelena opulenta L. KOCH. 3. The contents in the intestine, Marpighian tube and rectal bladder of spiders bred in the different conditions were compared. The influences of starvation and humidity on the osmotic pressure of the blood and the rectal bladder fluid were investigated. 4. It was recognized that the liquid part in the rectal bladder decreased and the osmotic pressure increased more than that of blood did in accordance as the days of starvation increased and humidity lowered. 5. The results obtained seem to suggest that the rectal bladder plays a role of the active reabsorption of water.
In the brain of the brown dog tick, Rhipicephalus sanguineus (LATREILLE) 15 groups of neurosecretory cells are divided into 2 types, β and α cells. Among β cells, the function of the groups 2-5 in the dorsal ganglion are correlated with ecdysis, whereas group 18 in the ventral ganglion is required for the normal development of most tick tissue. Cells of groups 6, 72 and 71 (α-cell), 8-9, 10, 11, 12, 13, 14, 15, 16 and 17 are possibly related to digestion and maturation of the reproductive system respectively. The granules of β cells can be further divided into 2 groups by electron microscopy: large opaque droplets 1200Å-3000Å in diameter, and small opaque droplets 400Å-700Å in diameter. Lucent vesicles are also found.
The oribatid fauna obtained like Scheloribates, Lamellobates bengalensis, Archegozetes magna and Oppia yodai are numerically dominant. The total population of oribatid mites of both the plots exhibits an irregular trend of fluctuation which gives a maximum in July-August, a minimum in May and is more or less constant in November and December. Organic carbon content of the soil may increase the population density of oribatid mites.
Gamasamorpha cataphracta KARSCH, 1881 is redescribed on the types; synonym of it is Oonops corticalis BÖSENBERG & STRAND, 1906 (types examined; new synonymy). Pseudotriaeris n. gen. is described; type: Gamasomorphakarschi BÖSENBERG & STRAND, 1906), of uncertain affinities this genus is peculiar by the extreme complexity of the _??_-palp. Pseudotriaeris karschi (BÖSENBERG & STRAND, 1906) comb. nov. is redescribed on the types. From Formosa are recorded or described: Gamasomorpha cataphracta KARSCH; Ischnothyreus formosus n. sp. (_??__??_; type. loc.: Akau), near to I. narutomii (NAKATSUDI, 1942), distinguishable from this and the other species by the genitalia; Opopaea sauteri n. sp. (_??_, _??_ unknown; typ. loc.: Takao), near to O. syarakui (KOMATSU, 1967) comb. nov. (described as Gamasomorpha), distinguishable by the genitalia. Some considerations are made over taxonomical problems in the genera Gamasomorpha and Opopaea.