PACKARD.] PHYLLOPODS OF NORTH AMEEICA. 323 



evenly rounded in front and acute behind. In the 2d pair of feet the 

 2d eiidite is larger and much stouter than in A. longicaudatus ; the scale 

 of the 4th pair is large, broad, acutely ovate, the edges smooth, the 

 end only reaching to the outer third of the 5th endite ; the flabellum is 

 large, rounded, oval, while the gill is much as in the first pair. In the 

 10th i^air of appendages the endites are much as in A. longicaudatus, 

 but slightly broader, and the scale has the same relations to the 5th 

 endite as in A. longicaudatus. As regards the flabella, the two species, 

 though so much alike externally, differ decidedly in form, those of A. 

 lucasanus being larger and more rounded externally, while the gills are 

 narrower, and provided with scattered thick filaments on the edges, 

 which are wanting in A. longicaudatus. The under side of the telson, 

 which is longer, is also less spiny than in A. longicaudatus, and on the 

 upper side there are three spines in the middle instead of five, as in A. 

 longicaudatus, with two large spines on each side. Caudal appendages 

 less spiny than in A. longicaudatus; their spines are blunt, and their 

 arrangement into rows differs from that in A. longicaudatus, where the 

 rows are arranged in twos, a row of small spines being just behind a 

 row of large ones on the edge of the joint. Number of segments exposed 

 behind the carapace is 33 ; number of abdominal segments beyond the 

 last pair of apiDcndages, 13. 



Length of body, excluding the caudal appendages, 27™™. 



Length of carapace, 12™™; breadth of the same, 10™™; length along 

 the middle, 9™™. 



Length of the keel, 6™™; distance from front end of keel to front end 

 of carapace, 4™™. 



Length of caudal appendages, 14™™. 



Female. — The carapace is longer and the abdomen shorter than in the 

 male. There are 17 sx)ines on each side of the sinus of the carapace. 

 Telson as in the male, while the caudal appendages have smaller spines; 

 beneath not spined, being smooth, with a row of fine teeth on the edge. 

 The exites of the 11th ovigerous feet are decidedly shorter and broader 

 than in A. longicaudatus. Number of segments beyond the hinder end 

 of carapace, 29 ; number of segments behind the last pair of append- 

 ages, 11. The eggs are of the same size as in LeConte's species ; they 

 are spherical, orange-yellow; the chorion thin, transparent; the yolk 

 granules rather large. 



Total length of body, 20"""; length of carapace in the middle, 10'"'". 



Length of keel, 6"""; distance from front end of keel to front edge of 

 carapace, 4'™"'. 



Length of abdomen behind the hind edge of the carapace, 14 inches. 



Several males from Museum of Chicago Academy of Sciences labeled 

 " Cape St. Lucas, J. Xanthus, 4." 



Six male specimens in a bottle received from Dr. Stimpson, and 

 marked " Kansas "? 5" ; in the same bottle were 13 females oi'A. aiqualis. 

 These conld not be distinguished from Cape Saint Lucas specimens. 



This species occurred in great abundance at Ellis, Kans., associated 

 with the other Phyllopods from this locality. It was collected in June 

 by Dr. L. Watson. The specimens are not distinguishable from my 

 types of A. lucasanus from Cape Saint Lucas, Lower California. 



Numerous specimens have also been received from Fort Wallace, 

 Kansas, through Prof. Joshua Lindahl. 



The occurrence of this species so abundant locally in Kansas, at Cape 

 Saint Lucas, is interesting. Fearing that some mistake had been made, 

 I have repeatedly compared the Cape Saint Lucas specimens with nu- 

 merous ones from Kansas, and have observed no differences; in com- 



