PROPAGATION OF CEETAIN ECHINODERMS. 



65 



trance of Port William, East Falkland Island, a number of speci- 

 mens of a pretty little species, Goniocidaris canaliculata, A. Agas- 

 siz (fig. 5). Tliis species has a general resemblance, at a first 

 glance, to Gidaris papillata, var. stokesii ; but the radioles are 



Fig. 5. 



Goniocidai'is canaliculata, Agassiz. Twice the natural size. 



thinner and much shorter, and differ wholly in their sculpture ; 



the shell is even more depressed ; the secondary tubercles are more 



distant ; and a very regular series of short club-shaped rays seated 



on miliary granules are interposed in the rows between the 



spines of the second order. The ovarial openings are extremely 



minute, and are placed close to the outer edge of the ovarial 



plates. The upper part of the test is quite flat, the flat space 



including not only the ovarial plates and the plates of the pe- 



riproct, but the first pair, at least, of plates of each interambulacral 



area. Articulated to the primary tubercles of these latter are two 



circles of radioles, the inner more slender and shorter, the outer 



stouter and longer, but both series much larger than radioles 



usually are in that position on the test. 



7* 



