T3 



For the benefit of naturalists and others who might desire 

 to critically compare these two crayfishes, a closer description 

 of them is here appended: — 

 (r) Common Crayfish, Palinurus hugelii Heller. 



Carapace (body).^Armed generally with acute short spines of 

 varying heights, with the exception of the fore part, which 

 possesses five very large ones, the first in the centre and 

 forming the rostrum or beak, one on each side above the eyes, 

 of about the same size as the rostrum, and one under each 

 eye a little smaller than the three just mentioned. The spines 

 are generally relatively smaller, flatter, and not so acute in 

 larger specimens. The carapace is without setae (hairs) with 

 the exception of a short fringe on the hinder margin. (Rostrum 

 as large as spines above eyes.) 



Abdomen (tail). — Fairly uniformly smooth and without setae, with 

 the exception of a fringe along the hinder margin of each 

 segment. Small specimens usually have the segment pitted 

 here and there on their upper surfaces with small depressions, 

 larger ones possessing, in addition to these pits, small rough- 

 nesses or tubercles, the pits becoming usually somewhat reduced 

 in number. 



Te/50«.— (This forms the middle flap of the tail, properly so called). 

 Spiny. Without setae. 



Eye. — Rather elongate. 



Upper surfaces of legs. — Smooth and devoid of setae. A small spine 

 upon the end of the third joint of each leg, most prominent 

 on the first pair. 



(2) Southern Crayfish, Palinurus edwardsii Miers. 



Carapace (body). — Armed with spines, these being more acute and 

 longer than in Palimirus hugelii. There are five spines on 

 the front margin corresponding to those of Palinurus hugelii, 

 but the tw^o above the eyes (supra-orbitals) are by far the 

 largest, and a good deal larger than the supra-orbitals in the 

 latter species. The central spine forming the rostrum is usually 

 small and insignificant and strongly curved upwards. Each 

 spine, large or small, of the carapace is almost surrounded 

 with a fringe of setae (hairs). (Rostrum much smaller than 

 spines above eyes.) 



Abdomen (tail). — All of the segments are sculptured or excavated, 

 leaving broad flat irregularly oval or oblong eminences, each 

 of theee being partly surrounded by a fringe of setae. 



Telson. — (This forms the middle flap of the tail, properly so called). 

 Spiny; spines more numerous than in Palinurus hugelii. All 

 spines partly surrounded by a fringe of setae at their bases. 



