1895. 



PROCEEDINGS OF TEE NATIONAL MUSEUM. 



601 



To render the comparison easier, 1 liave tabulated the conditions, as 

 follows: 



SejiKil (lill'iroici'K of Hi/hlis (ja'mHxrdii. 



Length, lo iiiui. 



Superior anteniui' oue-tbinl leugth of binly. 



I'edimcle: Hairs not in tiilts. 



Iso friDge of long hairs at base ol' rtagclluiu. 



Inferior antenna' tliree-fourtlis leugtli of body. 



Length. 13.5 mm. 



Sujieridr antenna' one-lialf length of body. 

 Peduncle: I'ruslilike tufts of hairs. 

 Fringe of long liair.s at base of llagellum. 



Inferior antenna; IJ length of bixly- 



IVduncle: Four-fifths of Iiairs on the ventral i I'eduncle: Four- fifth.s of hains on the dorsal .side; 



side; no tufts of hair.s; third .joint not swolleti. 



Ineiibatory poneh jiresent. 



Last three segments of pleon separated from the 

 pereion by a slight annular constriction. 



llami of last ])leopodos bear no long hairs. 



Telsoii as long as broad. 



brush-like tufts of hairs; third Joint much 

 swollen. 



lneubator\ pouch absent. 



Last three segments of pleon .separated from the 

 pereion by a deep annular constriction. 



Inner ramus of last ]ilciiiiod(is li;is long liairs on 

 outer edge. 



Telson longer than lu-oad. 



A comparison of tlie preceding table with that of the two sexes of 

 Bijblis scrrata (p. 51)9) will farther illustrate the nature of the characters 

 tliat are, subject to sexual dimorphism. 



It will now be instructive to assume that the Newport specimens are 

 males of Bijhlis longicoruis, and to construct a provisional table exhibit- 

 ing the differences between the two animals. The table is as follows: 



Sesual differences of Byblis loiigiconiis. 



Length, 8 mm. 



Superior antenna; two-thirds length of body. 



Teduncle: Hair.s not in tufts. 



Xo fringe of U)ng hairs at base of dagelluni. 



Inlerior antenna^ U length of body. 



Length, 8.5 mm. 



Superior antenna- two-fifths length of body. 

 Teduncle: Hairs in brush-like tufts. 

 Fringe of long hairs at base of tiagellum. 



Inferior antenna' U length of body. 



Peduncle; Four-fifths of liairs on ventral side; no Peduncle; Xinetenths of hairs on dorsal side; 



tufts of hairs ; third joint not swollen. 

 Xine-tenths liairs on ventral side of Hagellun 



brush-like tufts of hairs ; third .joint very much 

 swollen. 

 Xine-tenths hairs on dorsa! side of riagellum. 



Incubatory ponch jiresent. 



Last three seginen s ot pleon separated from pi 

 reion b\ a slight annular constriction. 



Incub;itory pom^h absent. 



Last three segments of jileon sejiarated from pe- 

 reion by ;i dee]i ;iniiul;cr constriction. 



Kami of hist jileopodos bear no long hairs. 



'I'wo rami of bisl jdeopodos bear long hairs on botli 



..■dges. 



Telson broader than long. 



Telson twice as long as broad. 



