832 MR JAMES J. SIMPSON 



Traces of the canals passing to the polyps can be observed on the otherwise flat 

 sterile sides. 



The stem is traversed by several (about 12) narrow ccenenchymal longitudinal 

 canals, which are almost equally distributed from the centre to the circumference ; these 

 are supported by very thick walls densely packed with large tuberculate spindles. The 

 canals pass upwards and branch, so that each polyp is connected with the main portion 

 by means of solenia. 



The polyps are situated on the edge of the flattened disc (like the flowers in Celosia) 

 in 4-6 indefinite rows. Each is supported by a hollow cylindrical calycine portion 

 1*5 millims. in diameter, strengthened by large longitudinally arranged spindles, the 

 points of which project and form a protection for the completely retractile anthocodia. 

 An aberrant polyp arises near the middle of the sterile disc ; a slight ridge marks the 

 position of the canal from which it takes its origin, and it is possible that this might 

 have been the origin of a lobe similar to that at the base of the colony. 



The anthocodise (fig. l) are about 1 millim. apart, and when exserted, but with 

 the tentacles infolded, have a height of about 275 millims. and a diameter of 1*5 

 millims. The " crown and points " arrangement described by Professor Hickson for 

 Chironephthya is a very prominent feature. The "crown" consists of 7-10 rows of 

 curved spicules placed circumferentially and loosely interlocking. Surmounting this 

 there are eight triangular points, each consisting essentially of two large, slightly curved 

 spindles enclosing an acute angle and touching on their convex sides. Between these, 

 however, there are occasionally one or two smaller spindles disposed more horizontally. 

 When at rest, the tentacles are simply infolded and overlap one another ; when expanded, 

 they have a length of about 1 millim. ; their aboral surface is covered with small scale- 

 like spicules disposed " en chevron," but enclosing a very obtuse angle. 



Ova 0*3 millim. in diameter are very abundant on the mesenterial filaments, but, 

 in spite of their large size, they showed, even when stained, no trace of segmentation. 



The spicules are of three kinds, which correspond to the various positions in 

 the colony. The following are some of the measurements of length by breadth in 

 millimetres : — 



A. Stem and expanded sterile portion — transparent spindles densely covered with 

 compound warts (fig. 3a) — 



(1) Spindles markedly tapering — 2'2 x 0"55 ; 2 x 0"5 ; l"8x0'4. 



(2) Half-spindles or clubs— 1 -05 x 0'25 ; 0'8 x 0*3 ; 075 x 0'3. 



B. Anthocodise — pale yellow spiny spindles and scales. 



(1) " Crown"— warty curved spindles (fig. 36)— 0'95 x 0'18 ; 0'85 x 0"14. 



(2) "Points" — warty spindles straight, curved, or club-shaped (fig. 36) — 



0-95 x0-l ; 0-9 x0'15; 0'85 xO'l. 



(3) Tentacles — scale-like, with irregular edges ; many are constricted near the 



middle (fig. 3c) 0'08 x 0"02 ; 0'07 x 0*035 ; 0'06 x 0*02. 

 Locality. — Andamans. 



