SALFA. 13 



in the anterior pair, and with the left anterior one by means of 

 the two small dorsal spurs of the latter, and so on, for each suc- 

 ceeding pair, so that every individual of the chain is always con- 

 nected by spurs to the three immediately surrounding it in front, 

 on the side, and behind. 



As far as I have noticed, the chains remain connected till they 

 are fully grown, although the breaking up of the chain from any 

 cause does not prevent the components from living for a short 

 time, yet the chaiu, as a whole, is by far more active than the sep- 

 arate components when free. The largest chains I have seen are 

 somewhat over a foot in length ; in these the individuals meas- 

 ured about five eighths of an inch in length. This is much smaller 

 than the solitary forms, which attain a length of an inch. Sars 

 and Krohn were the first to rei)eat the observations of Chamisso 

 concerning the connection of the solitary and aggregate forms, and 

 they have clearly sIkjwu that the solitary form is asexual, al- 

 ways producing by buddhig a chain of Salpce which are the sex- 

 ual forms, and bring forth Init a single cml)ryo developed from an 

 egg, giving rise to the solitary form. Huxley, Leuckart, and Yogt 

 have also since shown the entire accuracy of the observations of 

 Chamisso, and have greatly hicreased our knowledge of the organ- 

 ization and development of these animals. The observations I 

 have made concerning the early development of the chain and the 

 solitary embryo are too fragmentary for publication, and I am in- 

 duced to give this description of our Safpa, in hopes of calling at- 

 tention to its existence on our coasts, and inducing those who are 

 more favorably situated than I am to develop further this interest- 

 ing subject. I would also add that this Sa/pa is not the only free 

 Tunicate frequenting our coasts ; two species of Appendicularia 

 are extremely common, which have thus far escaped the attention 

 of zoologists ; they are closely allied to A. furcata and A. long-i- 

 caiida; they both occur in Massachusetts Bay and Long Island 

 Sound, while the Salpa Caboti has not as yet been found farther 

 north than Nantucket. 



Explanation of Figures and Lettering.* 



a. Anterior opening. c.f. Ciliated fossa. 



b. Posterior opening. c. b. Ciliated band. 



e. Endostyle. ch. Small Salpa chain within form. 



n. g. Nervous ganglion. g. Gill. 



* These Figures of Salpa have a double numbering, one referring to the figures in this 

 work, the other bein<r the same as in the Boston Proeeedintrs. 



