PACKAED.] 



PHYLLOPODS OF NOETH AMERICA. 

 LiMNETis GOULDii Baird. 



299 



Plates II, Figs. 1-6 ; XXIX, Fig. 9. 



Limnetis gouldii Baird, Annals and Mag. Nat. Hist., 3d ser., vol. x, 393, 1862. 



Shell smooth, spherical, quite round, not often oval as in the two 

 succeeding species, and of a uniformly smaller size. 1st antennae very- 

 slender, not so broad at tbe end as in L. brevifrons. 2d antennae with 

 the stem longer and slenderer than 

 in the two following species ; the 

 upper flagellum 16, the lower 16- 

 jointed, with longer setae than in 

 the other species. First leg of 

 female with a very large, long, and 

 broad flabellum {br'), the posterior 

 division (br") very long and slen- 

 der, closely resembling the 6th en- 

 dite, but considerably longer; the 

 gill rather small. The coxal lobe 

 (1st endite) rather broad and not 

 so long as in the two other species ; 

 the hand is much slenderer, and 



the claw (6th endite) is longer and j,j^ i._LinmeHs gouUU, enlarged. Burgess del. lat 



slenderer than in L. mucronatus ; antennae not drawn. 



in the male the coxal lobe is considerably smaller and more triangular 

 and acute than in the two other species; the comb, or 4th endite (^*) is 

 armed on the edge with an inner row of small and a marginal row of 

 much larger digitate setiferous processes; the finger (P) is of moderate 

 size, and the claw-like 6th endite is long and slender; the flabellum {br ) 

 is about twice the size of the gill; aud its posterior process {br") is 

 long, narrow, extending only a little beyond the base of the 6th endite. 

 The front in the male (Fig. 3 d, in text) is truncated, but contracts below 

 the eyes more than in the other species; while the carina on the front 

 of the head is unusually high. In the female the rostrum ends in a shar]3 

 point, with lateral acute angles much as in sharply mucronate specimens 

 of L. mucronatus. 



Length of the shell, 3°^™; breadth, 2p™. 



The species was first discovered in "fresh water at St. Ann's, twenty 

 miles from Montreal, Canada." Collected by Charles Gould, esq., June, 

 1857 (Brit. Mus., W. Baird). The young received from Hanover, N. H. 

 Kear Boston, Mass. (Edward Burgess); near Providence, E. 1., in great 

 abundance in a pond which dried up in midsummer, occurring during 

 May, and for at least a month after BrancJiipus vernalis had disappeared 

 from the pond (A. S. Packard, jr., and H. C. Bumpus) ; abundant in a 

 pond at Glendale, Long Island, in March and April (Dr. C. F. Gissler) ; 

 IsTormal, 111. (S. A. Forbes) ; Eock Island, 111. (W. H. Pratt, Davenport 

 Academy). 



This is our most abundant species, and appears to range over Kew 

 England, Canada, westward to tbe Mississippi Eiver at Eock Island, 

 111. It is distinguished from the two other species by the more s])her- 

 ical shell, its smaller size, the rather narrow, contracted front of the 

 male, and by the differences in the antennae and legs indicated in 

 Plate II. 



We have kept these beautiful little phyllopods in confinement from 

 early in May until the middle of July, with few changes of water; 



