52 G REPORT OF (TOMMISSIONER OF FISH AND FISHERIES. 



produced iuto long spines, and the sixth segment with two dorsal spines. 

 The proportional size and the outline of the last segment are shown in 

 Figure B ; its ]30sterior margin is armed with a long and stout central 

 spine, and each side with fourteen or fifteen plumose spines or set*, which 

 are articulated to the margin. 



In this stage the young were first taken July 1, when they were seen 

 swimming rapidly about at the surface of the water among great num- 

 bers of zoene, megalops, and copeopods. Their motions and habits re- 

 call at once the species of Mysis and Thysanojjoda, but their motions 

 are not quite as rapid and are more irregular. Their bright colors ren- 

 der them conspicuous objects, and they must be readily seen and cap- 

 tured by fishes. They were frequently taken at the surface in different 

 parts of Vineyard Sound from July 1 to 7, and several were taken off 

 IsTewport, Rhode Island, as late as July 15, and they would very likely 

 be found also iu June, judging from the stage of development to which 

 the embryos had advanced early iu May in Long Island Sound. Besides 

 the specimens taken in the open water of the Sound, a great number 

 were obtained July 6, from the well of a lobster-smack, where they were 

 swimming in great abundance near the surface of the water, having un- 

 doubtedly been recently hatched from the eggs carried by the female 

 lobsters confined in the well. Some of these specimens lived in vessels 

 of fresh sea-water for two days, but all efforts to keep them alive long 

 enough to observe their molting foiled. They appeared, while thus in 

 confinement, to feed principally upon very minute animals of different 

 kinds, but were several times seen to devour small zoe?e,and occasionally 

 when much crowded, so that some of them became exhausted, they fed 

 upon each other, the stronger ones eating the weaker. 



Second stage. — In the next stage the young lobsters have increased! 

 somewhat in size, and the abdominal legs of the second to the fifth seg- 

 ments have appeared. The rostrum is much broader, and there are 

 several teeth along the edges. The basal segments of the antennulas' 

 have become defined, and the secondary flagellum has appeared, but is 

 not subdivided into segments. The antennte and mouth organs have 

 undergone but slight changes. The first cephalothoracic legs are propor- 

 tionally larger and stouter than in the first stage, and have become truly 

 cheliform. The succeeding legs have changed little. The epidodi of all 

 the legs and of the external maxillipeds have increased in size, and the 

 branchial processes are distinctly lobed along the edges, and have be- 

 gun to assume the form of true branchiae. The segments of the abdomen 

 have the same number of spines, but they are relatively somewhat 

 smaller, and the last segment is relatively smaller and broader at base. 

 The appendages of the second to the fifth segments differ considerably 

 in size in different sj)ecimens, but are nearly as long as the segments 

 themselves ; their terminal lamelLne, however, are represented only by 

 simple sack-like appendages, without sign of segmentation, or clothing 

 of hairs or seta?. The penultimate segment is still without appendages* 



