Miscellaneous, 327 MISCELLANEOUS. A new case of Care of the Brood in Holothurians. (Provisional Communication.) By Prof. Hubert Ludwig, of Bonn. The number of sea-cucumbers which care for their brood known up to the present time amounts to seven, all of which belong either to the Dendrochirotse or to the Syuaptidoe. One species among t\\Qm.—PhiiUophorus urna, Grubc — utilizes the body-cavity as a brood-chamber, while in the case of Cucumaria crocea (Lesson) and Psolus epliippifer, W. Thomson, the eggs undergo their development upon the dorsum of the mother ; in Cacumaria lievigata (Verrill) and Cucumaria glacialis, Ljungman, on the other baud, development takes place in special ventral brood-pouches (invaginations of the integument). With the exception of the Mediterranean Phijllo-pliorus urna, all these Dendrochirotse are arctic (Cucumaria glacialis) or antarctic iovms (Cucumaria crocea, 0. Icevigata, Psolus epliippifer). In the case of the two Synaptidae which care for the brood — Synapta vivipara (Qirstedt) and Chiridota rotifera (Pourtales) — both of which belong to the West-Atlantic marine region, the body-cavity serves as brood-chamber ; herein these species resemble Phyllo-phorus urna. With reference to Synapta vivipara, Clark* has recently furnished us with details of the development and care of the brood, after I had previously given a brief notice t of the gastrula-stage found by me in the body-cavity of this species. As regards Chiridota rotifera, we possess only the fragmentary obser-vations I published by myself in 1881 %. That, however, there also exists an antarctic Chiridota in which care of the brood is well-marked, I am now in a position to show. The species in question is Chiridota contorta, which was described by myself in the year 1874, and of which I have now before me a more extensive series of specimens from the Hamburg Museum (obtained by the Hamburg-Magellan Collecting Expedition). In this species I discovered a form of care of the brood hitherto unknown either among Holothurians or in the case of any other Echinoderm. For in the female animals (the sexes in this species are separat<i, just as I can also show to be the case in Chiridota * Clark, "The \i\i'pnvous Si/naj)ta of the West Indies" (Zool. Auz, 189G, p. 398), and "Notes on the Life-IIistory of Syiuqjta vivipara, CErstedt " (' Journal of the Institute of Jamaica,' vol. ii. part 3, Kings-ton (Jamaica), 1896, pp. 278-282). t Ludwig, " Die von Chiercliia auf der Fahrt der kgl. ital. Corvette ' Vettor Pisani ' gesammelteu Holothurien," Zoologiscbe Jahrbiicher, ii. 1886, pp. 28-29. Clark does not refer to this publication, but, on the contrary, erroneously asserts that I described a specimen of Synapta vivi-para as far back as 1881. My paper of the year 1881 (' Archives de Biologie,' ii. p. 41) refers not to hynapta vivipara, but to Chiridota rotifera. X See previous note.
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