PART 5 A MONOGRAPH OF THE EXISTING CRIXOIDS 727 



successive brachials, is much longer than as much as four tunes as long as the other; 

 the proximal and distal edges are strongly oblique, the former slightly concave, the 

 latter faintly convex and armed with small spines. It seems likely, according to Dr. 

 John, that the distal brachials of this species are strongly spinous. 



Syzygies occur between brachials 3+4, and usually 9 + 10 and 14+15. In the 

 few arms that remain unbroken some little way beyond the third syzygy the syzygial 

 pairs in that region are separated by one or two brachials only. The length from the 

 proximal edge of the IBri to the second syzygy is 8.0 mm. and the width at the first 

 syzygy is 1.2 mm. in the larger syntypes. 



In none of the specimens are any of the pinnules complete. P] is not nearly com- 

 plete in any of them; it has the first 4 segments short but the fifth is slightly longer 

 than broad. The following are descriptions of the best preserved pinnules of one 

 large specimen. P a is about 4 mm. long and is composed of 11 + segments. The first 

 segment is short, the second to fifth are as long as broad and a little compressed from 

 side to side, and the sixth to eleventh are more rounded and become progressively 

 longer and more slender. The sixth is nearly, the eleventh a little more than, twice as 

 long as broad. P 2 , a genital pinnule, is about 4 mm. long and consists of 9+ segments. 

 In another specimen it consists of 12 segments and appears to be nearly complete. 

 The first segment is broader than long, the second and third are about as long as broad 

 and of an irregular shape having a narrow dorsal edge, and the fourth and fifth are 

 longer than broad. The sixth is more than twice as long as broad and narrower distally 

 than proximally. The remaining segments become progressively more slender and are 

 three or more tunes as long as broad. The small gonad lies on the fourth to sixth 

 segments. P b is very like P 2 . P c is about 5 mm. long with 10+ segments. The first 

 and second segments are slightly broader than long, the third is as long as broad, the 

 fourth is nearly, the fifth quite, twice as long as broad, and the sixth is more than twice 

 as long as broad. The seventh to tenth are more slender and three or more times as 

 long as broad. There is a large gonad on the fourth to fifth segments. P 5 of another 

 specimen is 4 mm. long, with 8+ segments, of which the first is broader than long, the 

 second and third are slightly longer than broad, the fourth is twice and the fifth more 

 than twice as long as broad, and the sixth to eighth are three or more times as long as 

 broad. 



There are no side- or covering-plates on the one pinnule examined for them. 



Remarks.- Dr. John said that this is a small species, represented by five specimens, 

 all with the arms broken, one considerably smaller than the others. He remarked 

 that this species appears to be best placed in Thaumatometra although the number of 

 cirrals is greater than in any other species of the genus, in none of which, so far as is 

 known, do they exceed 22, as opposed to up to 30 in this species. 



[NOTE BY A.M.C.] As noted under the heading of Fariometra, I cannot agree with 

 this inclusion of sokotrae in Thaumatometra. The discrepancy in number of cirrus 

 segments seems to me to be too great to allow it. The majority of the species of 

 Thaumatometra have only about 15 segments in the longest cirri, although the very 

 large T. tennis may have up to 22. As for the proportions of the cirrus segments, 

 most of the species of Fariometra have the outer segments slightly longer than broad 

 also. However, the longest segments are relatively longer in sokotrae than in any 

 species of Fariometra except F. parvula, which is also marked off geographically from 

 the rest of the genus. Although the total number of cirrus segments is greater in 



