140 Messrs. T. and A. Scott on some 



The male anterior antennse are ten-jointerl, and the last six 

 are more or less modified for grasping ; the sixth and seventh 

 joints are very short, but the others are of moderate length. 

 Mandibles elongate, narrow, and with an oblique tooth-apex ; 

 the basal part of the mandible-palp is considerably dilated, 

 while the secondary joint is narrow and furnished with one 

 marginal and four terminal seta?. Maxilla3 and foot-jaws 

 nearly as in Ameira lomjipes. Tiie first pair of swimming- 

 feet are elongate and somewhat like those o{ Ameira longipes, 

 but the first joint of the inner branches is only about one 

 sixth longer than the combined lengths of the second and 

 third joints ; while the outer branches reach to near the 

 middle of the second joint of the inner ones (PI. IX. fig. 2). 

 In the female tlie inner branches of the next three pairs reach 

 to about tlie middle of the second joint, and are scarcely 

 equal to half the length of the elongate outer branches ; in 

 the male the inner branches of the third pair reach to the end 

 of the second joint of the outer branches, and each of the 

 three joints is rather longer and narrower than tlie joint that 

 precedes it, while the hist joint, besides being furnislied with 

 four long plumose marginal setse, is armed with a terminal 

 spine (PL JX. fig. 3). The basal joint of the fifth pair in 

 the female is broadly triangular, and its blunt-pointed apex 

 bears five setje, the second one of which, counting from the 

 outside, is very long, being more than double the length of 

 the seta on either side of it ; the secondary joint is oblong- 

 ovate, its greatest breadtli being equal to about two fifths of 

 the lengtli ; there are five setaj of variable length, ranged at 

 intervals from the middle of the exterior margin to the apex, 

 in addition to a very long intero-subapical seta ; the apex of 

 the basal joint reaches to about the middle of the secondary 

 one (PI. VIII. fig. 19). The fifth pair in the male are 

 smaller than those of the female, and both joints are propor- 

 tionally shorter and broader, and want the very long seta? of 

 the female fifth pair. Caudal stylets shorter than the last 

 abdominal segment and broadly pyriform ; the principal tail- 

 setae arc as long as the abdomen. 



Huh. Obtained by washing some black sandy mud near 

 low-water mark at iSeafield, in the vicinity of Loith, Firth of 

 Forth. 



lieinarks. Ameira exilis somewhat resembles Ameira lon- 

 gipes, Boeck, but is larger and more slender, and tlie propor- 

 tional lengths of the joints of the female anterior antennre 

 diil'cr considerably in the two species ; they also ditfer in the 

 proportional lengths of the branches of all the swiniming-fect. 



