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PROCEEDINGS OF THE 



[Dec, 1857. 



but thickest upon the upper portion of the body, were the brown 

 pustules, which are so conspicuous in that species of our harbor, 

 identified for the present with the Beroe punctata of Eschscholtz. 

 The chief distinction between these and the Bolina embryos, 

 however, was the complete absence of any trace of tentacula, or 

 tentacular chambers. 



The bi-labial mouth of these specimens was like that of Beroe, 

 and the labia were broader in proportion to the breadth of the 

 animal than in the Bolina embryos. Their motion, also, in swim- 

 ming was much more rapid. 



The condition of the circulatory system was quite different from 

 its condition, either in the adult Beroe or the embryo Bolina. 

 Above the digestive cavity was a single large octagonal cavity 

 like the digestive cavity of the young Cunina larva. The eight 

 points of this were distributed, one to each of the ambulacra. This 

 cavity, of course, corresponded to the two sinuses of the Bolina 

 embryo, and to the symmetrical apparatus of branched tubes in the 

 adult Beroe. The gastric tubes had already descended to the 

 margin of the mouth, where already existed a marginal tube, but 

 this latter was confined to the labium to which it belonged, and 

 did not anastomose with the corresponding tube of the opposite 

 side. On the other hand the marginal tube on each side anasto- 

 mosed at each of its two extremities with one of the two superfi- 

 cial tubes which approached the angles of the mouth on that side. 

 The two tubes intermediate between these, had not progressed 

 more than half way down the length of the animal's body, and as 

 in Bolina, all the superficial tubes outstripped the ambulacra in 

 the rapidity of their growth downward. In these embryos, which 

 were unmistakeably the young, either of Beroe punctata, or of 

 some nearly allied Beroid, the tubes were all very much broader 

 than in lhe Bolina embryos, and instead of being grouped in pairs 

 were equi-distant from each other. Unfortunately these speci- 

 mens perished before further information was obtained from them. 

 I will, however, notice a few peculiarities which may lead to their 

 recognition at some future date. The labia were bordered each 

 by a very distinct rather broad yellowish band. On each side of 

 the sense-capsule, at the superior pole, were two dark pigment 

 spots. The ambulacra were capable of being entirely retracted 

 and covered by the inter-ambulacras areas which would meet over 

 them. The motion in swimming was very brisk and lively. The 

 digestive cavity, as in Beroe, was very broad at the mouth, nar- 



