The Cricoids from Dr. S. Bock's P'xpedition to Japan 1914. 03 



flattened. 1 Brachials latei-ally with a sharp edge, never a niedio- 

 (lursal carinalion. 15 segments per cm. (12 — 18, if the syzygial pairs 

 are counted as units). 



Pi 2-i — ^25; 12,5 mm. smooth, 2'' — 4"' segment with a slight keel 

 <tn the side which faces the distal parts of the arms, Pg similar, P.^ 25, 

 12 mm. P5 21: 11 mm. P„ 23; 8 mm. P, — P5 without ambuiacral fur- 

 rows, larger and coarser than the other pinnules, with gonads. Nevei- 

 theless not so marked as in lY. afra macrodiscus. Distal p. +'d'd: 1-1 

 mm. (1"' to 2'" or 3' segment short, then L-l'2 — 2 X br). Disk 13 

 mm. Colour: red-violet. 



I have kept this Tr. encfinus 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. encrinus. According 

 to A. H. Claek (Siboga Exp. Vol. 4-2 B) Tr. encrhms is said to be restricted 

 to the teri'itories east of India, 2V. carinata to occur west 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 eirrals 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 eirrals, 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 1012 to keep the two 

 species separate. 



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

 that lie has examined present some variations in the relation between 

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

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

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

 liinge ohne weitei-es einsieht» that the relation between L and br of 

 the eirrals varies is not, however, quite coi'reet. The proportions l)et- 

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

 cals and length of cirri has vai-ied, 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. II. Carpenter has described a young specimen from Bahia 



