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an inch broad, and its body is composed of ten segments, 

 the last being almost absorbed in the ninth, which again 

 is much smaller than the eighth. Its activity was remarkable, 

 and its motion sinuous, like that of the Sole. The female is 

 about i of an inch long, and ^^ of an inch broad ; its cephalo- 

 thorax has five joints, and its abdomen six. On either side of 

 the abdomen, and springing from the junction of abdomen 

 and thorax is a bag of very numerous small eggs, about -^V ^^ 

 an inch long, and gV of an inch broad, of an elongated egg- 

 shape. The female, like the male, was extremely nimble and 

 active, and swam swiftly round and round the glass. The 

 eggsacs, while the animal was in motion, were made to rapidly 

 approach and recede from one another, thus appearing more 

 like organs of locomotion. Both sexes appeared to me to have 

 a finely granulated exterior, and a uniform dull lavender 

 colour. In the head of each were a pair of elongated bronze 

 red specks, the eyes according to Dana. 



The other animal which I examined was one of those very 

 curious Tunicates, the Saljoae democraticae. This Salpa, Mr. 

 Haswell writes me, " develops no sexual glands, but give 

 origin by budding to a chain of young " — Salj)ae mucronatae — 

 each differing considerably from Salpa democratica. These 

 remain, through life, united in a chain, and " each when adult 

 develops a single egg from which a Salpa democratica is 

 developed." The solitary Salpa which I had the good fortune 

 to capture, contained, when caught, a chain of young which 

 were distinctly visible through the transparent body of the 

 Salpa, curled round at the posterior end of the internal 

 cavity. Next morning, when daylight permitted a more de- 

 tailed examination. I found the chain of 80-90 minute S. micro- 

 natae just escaping from the S. democratica, the last pair of the 

 chain becoming detached a few moments after I got them under 

 observation. This chain consisted of a double row of animals, 

 so small that with my inferior magnifier I could only see them as 

 egg-shaped transparent masses, about ^V of an inch long, with 

 a purple knob at one end and a purple streak in the interior. 

 The chain was about If of an inch long, and floated with the 

 purple knobs uppermost, in a curved shape, which Yaried as 

 the individuals performed their occasional simultaneous con- 

 tractions. 



The Salpa democratica was about i an inch long, or f of an 

 inch, if the tapering conical processes at the posterior end are 

 included. Its breadth was about ^ of an inch, and its shape 

 that of a barrel, or square-ended egg. The tunic was perfectly 

 transparent, and the whole animal colourless, except the 

 main parts of the nervous system, which were of a beautiful 

 purple, and a few spots of a similar purple, which were, I 

 believe, parts of the digestive and reproductive organs. The 



