[From the American Journal of Science and Arts, Vol. Ill, June, 1872.] 



Brief Contributions to Zoology from the Museum of Yale College. 



No. XXL 



THE EARLY STAGES OF THE AMERICAN LOBSTER 

 (Homarus American us Edwards) ; by S. I. Smith. 



The majority of the published observations on the develop- 

 ment of the higher Crustacea have been confined to the changes 

 taking place in the embryo within the egg, or immediately after 

 leaving it. Of the later stages, which connect the newly hatched 

 young with the adult, little is known. So far as the published 

 accounts are known to me, this is the case in the history of the 

 common lobster of Europe. On the development of the lobster 

 of our own coast nothing has been published. The investiga- 

 tion, of which this article is a short notice, was undertaken to 

 supply this deficiency in the history of the later development 

 of the lobster, and is one of the results obtained through the 

 facilities for collecting and studying our marine animals, offered 

 last summer by the U. S. Commissioner of the Fisheries, Pro- 

 fessor Baird. 



The specimens were all obtained in Vineyard Sound, or the 

 adjacent waters, during July, and were mostly taken at the 

 surface in the day-time, either with the towing or hand net. 

 They present three quite different stages in the true larval con- 

 dition, besides a later stage approaching closely the adult. The 

 exact age of the larvae of the first stage was not ascertained, 

 but was probably only a few days, and they had, most likely, 

 moulted not more than once, perhaps not at all. Between the 

 third stage, here described, and the last, there is probably an 

 intermediate form wanting. The descriptions and figures have 



