The Ceinoids from Dr. S. Bock's Expedition to Japan 10 U. 93 



flattened. I Brachials laterally with a sharp edge, never a inedio- 

 dorsal cai-ination. 15 segments per cm. (I2^i;5. if the syzygial pairs 

 are counted as units). 



Pj 24 — 25; 12,0 mm. smooth, 2'' — 4"' segment with a slight keel 

 on the side which faces the distal parts of the arms, P^ similar, P3 25, 

 12 mm. Pr, 21; 11 mm. Pg 23; 8 mm. Pj — P^ without ambulacral fui'- 

 rows, larger and coarser than the other pinnules, with gonads. Never- 

 theless not so marked as in Tr. afra macrodiscus. Distal p. + 30; 14 

 mm, (P' to 2'^ or 3'' segment short, then L^l'/a — 2 X br). Disk 13 

 mm. Colour: red-violet. 



1 have kept this 7V. encrinus as a species, though it is obvious 

 that intermediate forms are to be found in territories between the re- 

 gion of distribution of Tr. carinata and that of Tr. encrimis. According 

 to A. H. Clark (Siboga F]xp. Vol. 42 Bj Tr. encrinus is said to be restricted 

 to the territories east of India, Tr. carinata to occur w^est of this peninsula. 

 In Crinoids of the Indian Ocean (1012) he is not of the same opi- 

 nion. In this work he certainly separates Tr. carinata from encrinus, 

 but of Tr. encrinus he says that it appears to the westward to Aden, 

 the Red Sea etc. About the cirrals he states that: »the outer seg- 

 ments are about twice as broad as long as in Tr. carinata». In the 

 Siboga work he distinguishes the species by the distal cirrals, which 

 in the former species are »much less than twice as broad as long» in 

 Tr. carinata: »more than twice as broad as long». It may be ques- 

 tioned which distinguishing feature he used in 1912 to keep the two 

 species separate. 



Reichensperger (1914 p. 107) states that specimens from Ceylon 

 that he has examined present some variations in the relation between 

 L and br of the cirrals. In a table he has given the cirrus-length 

 and the number of cirrals of the different specimens, but his assertion 

 that one »aus einem Vergleich der Gliederzahlreihe mit der Cirren- 

 länge ohne weiteres einsieht» that the relation between L and br of 

 the cirrals varies is not, however, quite correct. The proportions bet- 

 ween L and br might have been the same even if the number of cir- 

 cals and length of cirri has varied, for the coaseness of the cirrus is 

 also subject to variability. 



Reichensperger's second criterion of the identity ot the two spe- 

 cies (that P. H. Carpenter has described a young specimen from Bahia 



