124 



IIIROSIII OIISIIIMA 



IiRCOD-CARING IN I IOLOTI 1UKI ANS. 



In both cases, youngs were found contained in maternal body-cavity in a 

 few number and they seem to have been at a younger stage of develop- 

 ment than in the cases described by me. Of other holothurians, similar 

 cases have been known from three synaptids, viz. Synaptula hydriformis 

 (Lesueur) 8 and CJdridota rotifcra (Pourtalhs) 4 of Jamaica and adjacent 

 regions, and Lcptosynapta minuta (Becher) 5 of Helgoland. In the former 

 two species the youngs found in the body-cavity were very numerous, 

 especially in the second species in which above 500 were counted by Clark 

 in one case ; in the last species, which is of a very small size, only five 

 were found. 



As to the way in which the young escape from maternal body Clark 

 thought that a temporary rupture ocurring in the body-wall serves for 

 that purpose, while Becher 6 suggested that the abdominal pore, which he 

 proved to exist in Labidoplax buskii, might serve to export the young. 



Biological Laboratory, 



Fifth High School, Kumamoto. 

 Jan. 15, 1916, 



1) Kowalewsky, A. Beitrüge zur Entwicklungsgeschichte der Holothurien. Mém. d. 

 l'Acad. imper. Sci., St.-Pétersbourg, VII. Ber., Tom. XI, No. 6, 1867. Ludwig, H. Brutpflege 

 und Entwicklung von PhyUophorus urna Grube. Zool. Anz., Jahrg. 21, Nr. 551, 1898. 



2) Clark, H. L. The Holothurians of the Pacific Coast of North America. Zool. Anz., Bd. 

 XXIV, igoi, p. 162. 



3) Clark, H. L. Synapta vivipara : a Contribution to the Morphology of Echinoderms. 

 Mem. Boston Soc. Nat. Hist. Vol. V, No. 3, 1898. 



4) Clark, H. L. The De%'elopment of an Apcdous Holothurian — Chiridota rotifera. Jour. 

 Exper. Zool., Vol. IX, No. 3, igio. 



5) Becher, S. Über Synapta minuta, n. sp., eine brutpflegende Synaptide der Nordsee und 

 über die contractilen Rosetten der Holothurien. Zcol. Anz., Bd. XXX, 1906. 



6) Becher, S. Beobachtungen an "Labidoplax buskii (iM'Intosh). Z„w. Z., Bd. CI., Heft 1-2, 



1912. 



