290 A. K Verrill on Ascidians from New England^ 



The color of the masses, in 1 

 or bluish white, with yellowish ^ 



Eastport and Grrand Menan, with the last,— Expeditions of 

 1868 and 70. 



Amouroucmm pellucidum Verrill. 

 Alcyonidium ? pdlucidum Leidy, Journal PWl. Acad. Nat. Sciences, 2nd ser., toL 

 iii, p. 142, PI. X, fig. 25, 1855. 



"Polypidom translucent white, attached by narrow fascicu- 

 lated bases, which are extended in a procumbent manner and 

 then expand into wedge-shaped masses, upon the free, flat sur- 

 faces of which the polyps are clustered. Polyps with briglit 

 orange colored tentaculse. 



Attached to rocks, my till, sponges, etc., at Point Judith 

 (E. L); abundant. 



The masses of A. pellucidum from the white, fasciculated 

 points of attachment t,o the broad free surfaces are up to an inch 

 in thickness. Although I presei-\^ed a number of specimens in 

 fresh sea-water for some days, I could not induce the polyiVN 

 if they were such, to protrude from their cells, and I only \vd 

 the opportunity of examining them in their retracted conditi*'n 

 as represented "in figure 24, plate x." 



The figure referred to very well represents the thorax aud 

 abdomen of a species oi Amouroucium, allied to A. glabrum\., 

 except that the longitudinal ribs of the stomach were mistaken 

 for the retracted tentacles of a Bryozoan, and figured as such. 

 The post-abdomen is not shown, and was undoubtedly accident- 

 ally broken off in dissecting it out. 



The cloacal cavity, or atrium, is represented as distended bj 

 four large eggs, containing well advanced embryos ; the bran- 

 chial sac has a broad dorsal and 12 transverse ducts ; the int^es- 

 tine is like that of A. glahrum, and contained dark fcecal pellets, 

 the branchial opening has six rounded papillae ; the anal has an 

 elongated lobe ab<)v(> it. " rr 



Two specimens, dredo'cd at Wood's Hole, Mass. by Prot. ii- 

 E. Webster, appear to' be identical with this species. IH^J^ 

 form low, soft, broadlv expanded and flat topped masses, up t 

 2 inches in diameter, and -50 to 75 thick, attached by tne 

 middle of the lower surface and proliferous around the edge 

 the base, which is surrounded by young colonies, composea 

 but few individuals arranged around a central onnce - 

 covered externally with adhering sand. These young colonu|^ 

 are elongated, expanding to the truncate upper end, and a^c 

 very_ obliquely, the outer ones remaining free, except at oa^^ 



gelatinous, translucent, with but little adhering 

 increases toward the margin, and on the c 



