106 *S', I. Smith — Crustaceans of the Atlantic Coast. 



Stirapson (Marine Invertebrata of Grand Manan, p. 58), reports 

 this species (with an ?) as " very abundant in the waters at the mouth 

 of the Bay of Fundy, swimmino- near the surface in swarms." I have 

 never seen specimens from the Bay of Fundj, and, during several 

 seasons spent there, I have never observed any species of Mysis 

 swimming at the surface, as described by Stimpsoii. Thysanopoda 

 JSforvegica and inerniis, however, were found in vast numbers in pre- 

 cisely the same way as the Mysis is said by Stimpson to occur, and 

 it is possible that Stimpson, without making a special examination, 

 mistook the vast swarms of Thysanopoda for Mysis oculata. 



Mysis Americana Smith. 



Mysis Americana Smith, Report on the Invertebrate Animals of Vineyard Sound. 

 Report U. S. Commissioner of Fish and Fisheries, part i, p. 552 (258), 1874. 



Great Egg Harbor!, New Jersey, 1871, — in pools on salt-marshes, 

 and in great abundance in the stomachs of the ocellated flounder 

 {Chmiopsetta ocellaris), the spotted flounder {Lophosetta maculata), 

 and the shad. Stomach of shad !, Great South Bay, Long Island, 

 May 21, 1875. New Haven!, Connecticut, — abundant among sea- 

 weed, etc.. May, 1873 (A. E. Verrill and D. C. Eaton) ; and in great 

 abundance among hydroids, etc., under wharves, May, 1875 (S. F. 

 Clark) ; also dredged in 4 to 5 fathoms. Vineyard Sound !, young 

 occasionally taken at the surface in summer, 1871, 1875 ; also in the 

 dredge from 25 fathoms, but probably taken on the way up ; and 

 common in the stomachs of shad, mackerel, and sea-herring. Port- 

 land Harbor !, Casco Bay, taken at the surface and dredged in :3 

 fathoms, mud, 1873. 



This species breeds during the spring and summer, and very likely 

 during the larger part of the year, since the young and old are often 

 found together in spring and summer. The males are nearly or 

 quite as large as the females. Females carrying eggs or young vai'y, 

 in a large lot from New Haven, from 10 to H'"'" in length, and many 

 of the males in the same lot are of the latter length. One egg-carry- 

 ing female from Casco Bay is only 9-5""" long. 



The Americana is closely allied to 31. vulgaris of Europe, but is 

 very readily distinguished by tiie telson, the lateral margins of 

 which are armed with spines of nearly uniform size in vulgar is.^ while 

 in Americana they are ai'nied with stout spines alternating with 

 intervals of several smaller ones. There are numerous other, but less 

 conspicuous differences. 



