192 CALIFORNIA ACADEMY OF SCIENCES. 



specimens were infested with a parasitic Isopod attached 

 to the under side of the abdomen. The color varies in 

 living specimens from olive green to olive brown; the 

 legs are reddish, and in many specimens there is a 

 light-colored dorsal stripe along the middle of the body. 

 The specimens were taken June 25, 1895; most of the 

 females were carrying ova. 



Family HIPPOLYTID^. 



Eostrum generally prominent. Eyes not covered by the carapace. Man- 

 dibles with or without a cutting edge and palp. First pair of legs chelate 

 and stouter than the second pair which is also chelate and has the carpus 

 annulated. 



The genera of this family need a thorough revision. 

 The genus Hippolyte has long been a sort of receptacle 

 for a large and somewhat miscellaneous assemblage of 

 forms. Bate has instituted several new genera for many 

 of the species but several more will doubtless be required. 

 Most of the Pacific species of this family fall naturally 

 into a group which I have characterized as the genus 

 Heptacarpus . 



Genus Hippolyte Leach. 



Carapace produced into a laterally compressed, serrated rostrum which 

 is excavated at the under side of the base. A supraorbital and antennal 

 spine present. Ocular peduncles short. First joint of the antennular 

 peduncle excavated above and armed with an external basal spine; second 

 and third joints subcylindrical, the terminal one supporting two flagella, 

 the outer of which is the shorter and more robust. Antennal scale with a 

 spine at the distal end of the outer margin. Third maxillipeds with a 

 short exognath and having the last joint armed with spinules at the tip. 

 First pereopods short and stout with the carpus excavated at the extrem- 

 ity to receive the base of the hand. Second pair slender, a little longer 

 than the first, and having the carpus three- jointed. The three following 

 pairs of legs decrease slightly in length posteriorly; dactyls spinulous 

 below. Abdomen smooth, the third segment posteriorly produced in the 

 median dorsal line and somewhat arcuate. Branchias five. 



Type. — H. varians Leach. 



