132 ToKio Kaburaki 



ranges from tlio southern seas to Idzn, and Safole toeniura to Misaki. 

 Tliere can be seen a number of forms limited in distribution to the 

 soutli of tlie Kumano, or the Yenshu Sea, such as Corias aygula, 

 Thalassoma hitescens. Chei'h'o inermis, Parahderes prionuritf^, BoJif-fes 

 CO pi stratus, etc. 



As they proceed southwards, ascidians seek a lower level of the 

 sea for their habitat. The species which are frequently to be met with 

 are Halocynthia mirahiUs, Molcjula vannamei, M. harfmeyeri, etc. 

 Of these the first is found to extend to as far north as Misaki. 



Echinoderms are very much in evidence, presenting to us a number 

 of species which inhabit the southern trojiical seas. Such are Opliiarach- 

 neJIa infernaJis, Ophiactis modesta, Ophiocentrus verticillatus, Ophiura 

 fageUata, etc. of brittle-stars ; Antlieneoj pentagomda, OuJcito, novoe- 

 guineoe, Ghoriaster gramilatus, Gymnaderia carinifera, Asterina 

 novoe-zelandioe, Pahnipes rosaceus, Luidia macidata, etc. of star-fishes ; 

 Diadema setosum, Echinothrix ccdcmiaris, Heterocenirohis mammilatus, 

 Strongylocentrotus purptireus, Toxopneustes pileolus, Laganum decago- 

 naUs, ScMzoMer japonicus, Maretia planvlafa, Lovenia eJongata, Meta- 

 lia maadosa, etc. of sea-urchins ; Bathyplotes onosehyi, Midhria ecJii- 

 oiites, M. onacidoia, Holotlwria orgus, H. cmerascens, H. edidis, SticJio- 

 pus nnanas, Thyone sacelhis, etc. of sea-cucumbers. Amongst them 

 some forms are found to extend north up to tlie middle zone. 



Coming now to crustaceans, we find some crabs, like Scylla serrafa, 

 Neptu'ims pelagicus and Trapezia, which are representative forms in the 

 tropical seas and extend their range northwards to about Loochoo and 

 Kyushu. This similarity holds also true of some species of Palinurus, 

 like P. fasciatus, P. ornatus, and P. biirgerii ; they appear to cease to 

 exist north of the Shiwo-no-misaki. Besides, there can be seen a 

 nunjber of })rawns which are of great commercial value, such as Penaeiis 

 japjonicns, P. semis?dcatus, P. ononoceros, P. curvirostris, and P. 

 velutinus. They are found spread into the middle zone. 



The most common ear-shells are Haliotis ovina, H. asinina, and 

 H. diversicolor, of which the first two have their northern limit near 

 Amami-Oshima, differing from the last species which is known to 

 extend to as far north as the shore of Ohiba prefecture. Oftentimes to 

 be met with in this district are some terebrids, like Terehra nehulosa, 

 T. suhdata, T. dimidiata, T. maculata, T. cremdata, etc. Of these the 

 larger species are confined to the neighbouring coasts of the islands of 

 Formosa, Loochoo, and Bonin, Avhile the smaller abound in the region 



