192 ANCEID.E. 



basal joints followed by two longer ones, the fourth being- 

 somewhat larger than the third, and followed by a slender 

 setose six-jointed flagellum. The inferior surface is 

 covered by two pairs of appendages (the gnathopoda), 

 the outer of which appears to consist of only two distinct 

 joints, although traces may be observed of their being 

 composed of several joints closely soldered together 

 (fig. g. $). The first of these joints is rather wide, flat- 

 tened, and considerably angulated beyond the middle, the 

 basal half being more curved and the distal half nearly 

 straight ; this is followed by an elongate-ovate joint, 

 setose at its extremity; and in certain positions we 

 perceived an indication of a very minute apical articu- 

 lation amongst the terminal setae. Within this pair of 

 appendages lies a pair of extremely delicate, flat mem- 

 branes, which we have above regarded as the anterior of 

 the incubatory scales, and within these are a second pair 

 of appendages (first pair of gnathopoda), similar in form 



