160 BULLETIN 8 2, UNITED STATES NATIONAL MUSEUM 



Dr. Gisl6n described as manca a specimen from Kiu Shiu (Bock's station 19) in 

 which the cirrus segments are never longer than broad; it is smaller than the specimens 

 of disciformis from shallower water, but in spite of that has shorter cirrus segments. 

 He remarked that the larger disciformis seems also to have fewer arms in proportion 

 to the length of the arms. He suggested that a differential character of value might 

 be found in the distribution of the syzygies. In disciformis, according to him, the 

 syzygies are separated by 3 or 4 muscular articulations, whereas in manca they are 

 separated by 9 or 10. He noted that this difference is also to be found in the original 

 descriptions, in which disciformis is said to have an intersyzygial interval of 2-6 

 brachials, that of manca being 4-10 (usually 7 or 8) brachials. He said that disciformis 

 seems to be more slender than manca and to have longer and narrower distal pinnules. 



Gislen remarked that the cirri in a specimen from Bock's station 59 identified by 

 him as Cyllometra albopurpurea somewhat resembled those of C. manca, raising some 

 doubt as to whether the two species are distinguishable. He said that this specimen 

 corresponds in all other characters with another, which is a younger individual of the 

 same type, but has pronounced albopurpurea cirri. Nevertheless, he said, certain 

 differences may be given that speak in favor of albopurpurea as a species. In the 

 specimen that he recorded and described as C. manca (from Bock's station 19) there 

 are 25 cirrus segments in a cirrus 11 mm. long, and the segments are broader than long. 

 He said that albopurpurea does not have the same number of cirrus segments until the 

 cirri reach a length of 15 mm., and the proximal cirrus segments are longer than broad. 

 He remarked that both the species during their evolution show a tendency toward short 

 cirrus segments, but reach this stage at different cirrus lengths. He said that the 

 characteristic dorsal spine of C. albopurpurea (and C. gracilis) is, in a somewhat 

 similar form, to be found in the specimen from Bock's station 19 recorded as C. manca, 

 though elsewhere referred to by him with some doubt as C. disciformis. Speaking of 

 the young stages he said that young individuals of albopurpurea have more than 10 

 arms at an arm length of about 15 mm. when the brachials are still very juvenile, long, 

 and strongly hourglass-shaped. The young of disciformis even at an arm length of 

 25 mm. have 10 arms and rather smooth brachials. 



Regarding his new species, Cyllometra pulchella, Gislen said that it most nearly 

 approaches C. manca from which it differs in having a smaller and less discoidal centro- 

 dorsal, longer cirrus segments which have only inconspicuous carinations, in the 

 absence of IIIBr series, in the short intersyzygial interval, and in Pj being almost 

 smooth. He said that the small transverse carination on the proximal cirrus segments, 

 which on some segments is replaced b}^ a pair of microscopic tubercles, proves that 

 pulchella is an oligophreate form, though otherwise it presents much that reminds us 

 of certain species of Perometrinae — for instance, the relatively large size of the central 

 cavity of the centrodorsal and the position of the rosette, which only radially forms 

 "spoutlike" processes. 



He remarked that in C. pulchella it is not always the largest specimens that have 

 the most arms, but rather the reverse. He said it is probable that the question of 

 catching the food plays a certain role; but possibly one might also connect the phenom- 

 enon with the fact that the family Colobometridae tends strongly toward a 10-armed 

 type, and that this is reached only through a transition stage with more than 10 arms. 

 However, he considered this not very likely, as he had often seen "duplicative" regen- 



