EEPORT ON THE OPHIUROIDEA. 261 



Table of Species of Gorgonocej)halus. 



One madreporie shield inside the raised mouth ring, and at base of a mouth | ,, 



angle. Disk covered by a line, close, smooth granidation, . . | (-orgonocephalus arhoresceii,. 



Disk set above and below with short toothdike spines, which are longer ) „ , , , 



and closer on radial shields, . . . . . . / Crorgonocephalus Jamarckn. 



Disk with small, smooth, scattered grains, which are more numerous on ) „ , , 



the radial shields ( '^'^''ffonoeepnahts eiicneims. 



Stands between the preceding and Gorrjonocephaliis agassizii (var. of I ,, , , 



Gorgonoeephalus eucnemis (X), . . . ■ • j ^^'"Vonocephahis malmgrena. 



Similar to GorgimocepiJialus euairmig, but with closer, more regular granula- ) ^ , , 



tion, and a strong row of grams along genital openings, . . j Gorgonoeephalus caryi. 



Disk set with a few small, irregular stumps, which are most numerous on 1 „ , , 



outer ends of radial sliields, / Gorgonoeephalus agassizii. 



Disk above closely beset with sliort, thick, thorny stumijs ; and below 1 „ 



with very smaU short spines, . . . . ^"^ Gorgonocephalu 





c3 

 T3 < 



o 



3 



e 



1=1 

 O 



>^ 



O 



us linckii. 



Disk similar to Gorgonoeephalus linckii, but smooth below, . . Gorgonoeephalus stimpsoni. 



Disk set above with scattered minute conical stumps, or stump-like ) ^ , , 



granules. Arms in the adult nearly smooth, . . .] Gorgonoeephalus poiirtalesu. 



Similar to Gorgonoeephalus pourtalesii, hut structure more delicate. The \ 



young has a simple under arm plate, which is in several jiieces in l Gorgonoeephalus chilensis. 

 Gorgonoeephalus piourfalesii, . . . . . . j 



Disk finely and smoothly granulated, and set, together with uijper surface ) ^ , , 



of arms, with large smooth tubercles, . . . /^ Gorgonoeephalus verrucosus. 



Radial shields set with fluted stumps. Tentacle scales flat, and strongly | ^, , , , , . 



toothed at the end, . . . . . . . / Gorgonoeephalus austrahs. 



Large conical spikes on upper disk, and upper surface of arms, . . Gorgonoeephalus mueronatus. 



Five madreporie shields, one at inner angle of each interbrachial space. Surface ) ^ , , 



of disk and arms smooth, . . . . . "^ Gorgonoeephalus eaeaohcus. 



Gorgonoeephalus pourtalesii, Lym. (PI. XLV. figs. 2-5). 



Astrophyton Pourtalesii, Lym., 111. Cat. Mus. Comp. ZooL, No. viii. part 2, p. 28, pi. iv. figs. 



41-43, 1875. 

 Astrophyton Lymani, Bell, Proc. Zool. Soc, p. 99, January 1880. 



Thia widely spread animal is found from Heard Island to East Patagonia over a region 

 between long. 70° E. and long. 70° W., 220 degrees in all, or more than half round the 

 southern end of the world. The western specimens from Heard and Kerguelen Islands 

 usually have the disk spines sharper and more numerous ; and the basal shafts between 



(zool. chall. EXP. — PAKT XIV. — 1882.) 34 



