Dendrocoelopsis americana (HYMAN, 1939), a troglophilic species of freshwater planarian, is known from several cave waters and springs in Oklahoma and Arkansas, U.S.A. The species has many eyes, arranged in two almost parallel longitudinal rows. Eyeless specimens of this species were collected from Soda Water Well, near Rockwall, Rockwall County, Texas. Morphological and histological descriptions of our material are given in the present paper, together with some considerations about its taxonomy and geographical distribution.

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A trematode, Acanthatrium ovatum and nematodes, Strongylacantha pretoriensis, S. rhinolophi and Porrocaecum sp. (larval form) were isolated from the bat, Rhinolophus cornutus cornutus, collected in the caves of various places in Japan, and the morphology of larva of Porrocaecum sp. was described.

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The present report is a description of the larval development of a hippolytid shrimp, Eualus leptognathus (STTMPSON) under laboratory conditions. It is one of the common species of Zostera beds in the vicinity of Miyazima Aquarium and the ovigerous females are observed from November to the next May there. This is the second Japanese species of this genus, in which the larval development is completely known. Like the other species, E. sinensis (Yu), the present species has nine zoeae and one megalopa stage and an exopod on the first three pereopods in ninth zoea stage. The species of this genus are divided into two groups by the number of pereopodal exopods in the last zoea stage. Except for two unidentified species from Kamchatka, only three, E. gaimardii and these two Japanese species, have an exopod on the first three pereopods in the last zoea stage. They, however, show rather apparent morphological differences, as well as discrepancies of the number of zoeal stages. E. gaimardii has only five zoeal stages and well developed rostrum in all larval stages. Moreover the larvae of these two Japanese species are readily distinguished from each other by the presence or absence of the rostrum, the pterygostomial spine, small spines on the ventral margin of carapace and outer spine on the antennal scale, by the shape of supraorbital and antennal spine, by the number of the lateral spines on the telson, etc. (Table 2). These considerable range of larval characters in the genus Eualus may reflect wide variations of the adult morphology.

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Four zoeal stages of Parapilumnus trispinosus SAKAI and Pilumnus minutus (DE HAAN) were described and illustrated in detail. Zoeae of the two species differ from those of the other members of the subfamily Pilumninae in having four pairs of mid-lateral spines on the abdominal segments II to V. Zoea of P. minutus is very similar to that of P. trispinosus, but easily distinguishable from it by having a pair of lateral spines on carapace. Zoeae of these species were compared with those of the other members of the Pilumninae. Main differences among the ten species which zoeae are known may be seen in the type of antenna II, the presence or absence of carapace spines and of mid-lateral spines on abdominal segments and, the type of telson.

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Four species of eriophyid mites injurious to garden trees are reported from Japan. Of these species, Aceria pseudoligustri, Diptilomiopus gilibertiae, and Diptacus crenatae are described as new, and Phytoptus emarginatae (KEIFER), new to Japan, is redescribed.

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Two new species, Tyrannochthonius similidentatus and Cheiridium aokii, are described from the Ogasawara Islands, and Nipponogarypus enoshimaensis is newly added to the fauna of the same islands.

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