180 THE MEDUSAE. 



The largest specimen measures 5 mm. in height by 4 mm. in diameter; 

 the smallest, 2 mm. high by 1.5 mm. in diameter. The bell has a triangular, 

 pointed, apical projection ; the gelatinous substance is very thin. 



Tentacles. — The tentacles, when extended, are about as long as twice the 

 bell height. Close to the base they are naked ; but for the remainder of 

 their length they are clothed with well-developed nematocyst swellings 

 which often form rings entirely surrounding them (PI, 43, fig. 8). When 

 the tentacles are extended these rings present the appearance of strings 

 of small beads. At the tip of each tentacle is a broader terminal swelling 

 crowded with nematocysts. The tentacles arise from swollen bases, each of 

 which bears an ocellus on its outer (aboral) face (PI. 43, fig. 8). 



The manubrium hangs about to the bell opening in all the specimens ; 

 but as in several it is evidently distorted by contraction, it is probable that 

 it could be considerably protruded in life. The mouth is surrounded by a 

 simple circular lip (PI. 43, fig. 9). There is no peduncle. There is a broad 

 triangular, apical extension of the manubrium, above the level of the origin 

 of the radial canals, conforming in outline to that of the apical projection of 

 the bell, and at its tip sufficiently attenuated to suggest the remnants of the 

 " stiel canal." 



Gonads. — A study of transverse sections of the manubrium has demon- 

 strated that the gonads are uninterrupted in either the perradial or interra- 

 dial planes, and are thus of the typical Sarsia type. In surface views of the 

 manubrium of several specimens there appear to be definite interradial 

 swellings (PI. 40, fig. 9), which I at first believed indicated the location of 

 the gonads ; but sections show that these apparent swellings are nothing 

 more than longitudinal ridges caused by contraction. In females the eggs 

 are very large. Two specimens had discharged their sexual products, leav- 

 ing the manubrium thin-walled and flexible. The gonads occupy nearly the 

 entire length of the manubrium, leaving only a short basal region bare. 



Color. — In life the region of the gonads is reddish brown ; the entoderm 

 of the tentacle bulbs Vandyke brown ; the ocelli black (PI. 40, fig. 1). 



Sarsia coccometra differs from the typical members of the genus in the 

 apical prolongation of the manubrium, in which it resembles Stauridium, and 

 in the possession of a well-marked apical projection, as well as in the high 

 development of the tentacular nematocyst bands. Its relationship, among 

 described genera, is evidently closest with Sarsia, and, on account of the 

 presence of the apical projection, with those species of the genus formerly 



