219 



littoral form, occurring, as a rule, close to the beach in shallow bays, sometimes 

 also in rockpools or in more or less brackish water. 

 Distribution. Bay of Keel (Giesbrecht). 



140. Ameira simplex, Scott. 



(PI. CXLIV). 



Ameira simplex, Norman and Scott, New Crustacea from Devon and Cornwall. Ann. Mag. Nat. 



Hist. ser. 7, Vol. XV, p. 291. 



Specific Characters. Female. Body moderately slender, with the 2 chief 

 divisions of almost equal length. Cephalic segment scarcely longer than the 3 

 succeeding segments combined, and conspicuously narrowed in front. Last caudal 

 segment about the length of the preceding one. Caudal rami somewhat longer 

 than they are broad and transversely truncated at the tip. Eye apparently want- 

 ing. Anterior antennse comparatively short, scarcely exceeding half the length of 

 the cephalic segment, the 2 basal joints much the largest and combined almost 

 as long as the remaining part of the antenna. Posterior antennae with the basal 

 part imperfectly subdivided. Mandibular palp comparatively small, with only a 

 single seta inside the basal joint. 1st pair of legs with the outer ramus some- 

 what exceeding half the length of the inner, terminal joint of the latter very 

 slender, about twice as long as the 2nd and scarcely shorter than the 1st, setae 

 inside these joints unusually long and distinctly ciliated. 3rd pair of legs with 

 the terminal joint of inner ramus almost as long as the other 2 combined, and 

 provided inside with 3 natatory setae. Terminal joint of outer ramus in the 4th 

 pair of legs likewise with 3 setae inside, the outermost of which however is very 

 small. Last pair of legs with the distal joint oval in form, slightly narrowed 

 towards the end, inner expansion of proximal joint extending to about the middle 

 of the distal joint and provided with 5 setae, the outermost out one much the 

 longest. 



Colour whitish. 



Length of adult female 0.60 mm. 



Remarks. This species has been recently described by Th. Scott in the 

 above-quoted Journal, and the following year it was also figured in a separate work 

 "On Crustacea from Devon and Cornwall". It is a somewhat anomalous form, differing 

 in several respects conspicuously from the preceding species, and approaching the 

 new genus Parameira (see below), to which it perhaps more properly should be 

 referred. The shape of the last pair of legs however seems to agree better with 

 that found in Ameira. 



