EXPLANATION OF THE PLATES. 

 Plate XVIL Perissopus communis Rathbun, and variety s^impsom" Rathbun. 



Fig. 19, Dorsal view of female of communis; fig. 20, Dorsal view of variety stimpsoni; 

 fig. 21, Ventral view of carapace, showing large knob opposite first maxillipeds; fig. 22, 

 Mouth tube and second maxilla; figs. 23 to 25, First, second, and third swimming legs; 

 fig. 26, Rami of third leg, enlarged; fig. 27, Fourth swimming leg; fig. 28, Rami of same, 

 enlarged; fig. 29, Fifth swimming leg; fig. 30, Ventral view of genital segment and 

 abdomen, showing abdomen (a), cement glands (c. g.), spermatophores is) in position, 

 and semen receptacle (s. r.); fig. 31, A single spermatophore, enlarged. 



Plate XVIII. Male chalimus of Perissopus communis Rathbun. 



Fig. 32, Dorsal view; note especially the eyes and the large gland at the base of the 

 frontal filaments; fig. 33, Ventral view of carapace, showing first and second antennse 

 and their adhesion pads; figs. 34 and 35, First and second maxillipeds; figs. 36 to 39, 

 First, second, third, and fourth swimming legs. 



Plate XIX. The female of Echthrogaleus coleoptratus Ciuerin. 



Fig. 40, Dorsal view; fig. 41, First antenna; fig. 42, Mouth tube and second maxillae; 

 figs. 43 and 44, First and second maxillipeds; figs. 45 to 48, First, second, third, and 

 fourth swimming legs; fig. 49, Ventral view of genital segment and abdomen, showing 

 abdomen (a), cement glands (c. </.), and sperm receptacles (s. r.); fig. 50, Ventral 

 view of genital segment with abdomen removed, showing sixth segment plate and 

 fifth legs. 



Plate XX. The female of Echthrogaleus deiiticulatus Smith. 



Fig. 51, Dorsal view; fig. 52, Second antenna; fig. 53, Mouth tube and second maxilla; 

 figs. 54 and 55, First and second maxillipeds: figs. 56 to 59, First, second, third, and 

 fourth swimming legs; fig. 60, Ventral view of genital segment and abdomen. 



Plate XXI. The female of Echthrogaleus torpedinis, new species. 



Fig. 61, Dorsal view, egg strings 40 mm. in length; fig. 62, Second antenna; fig. 63, 

 Mouth tube, second maxillae, and the large spines posterior to the latter; fig. 64, Second 

 maxilliped; figs. 65 to 68, First, second," third, and fourth swimming legs; fig. 69, 

 Ventral view of genital segment with abdomen removed, showing the sixth segment 

 plate and rudimentary fifth legs. 



Plate XXII. The female of i)me?nato-a/ero;r Kroyer. 



Fig. 70, Dorsal view, egg strings 120 mm. in length; figs. 71 and 72, First and second 

 maxillipeds; fig. 73, Mouth tube and second maxillae; figs. 74 to 77, First, second, third, 

 and fourth swimming legs; fig. 78, Ventral view of genital segment and abdomen, 

 showing abdomen (o), cement glands (c. g.), semen receptacle (s. r.), and sixth segment 

 (x), with its rudimentary legs. 



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