0KCHK8T11)-K. 5 



peudage. The cox* are largely developed. The tluee posterior 

 pairs of pleopoda are short and robust, the last unibranched. 



1. TALITRUS. 



Talitnis, Latr. Hist. Crust, vi. p. 229. 



Orchestia, Fr. Midler, Archiv fiir Naturgeschichte, 1848. 



Upper antennce not reaching to the extremity of the penultimate 

 articulation of the peduncle of the lower. Lower antennio having 

 the two basal articulations absorbed in the fi'ontal wall of the head. 

 Mandibles not palpigerous. Maxillipeds not unguiculate. First 

 pair of gnathopoda not subchcliform in either sex ; second pair 

 of gnathopoda rudimentary and imperfectly subcheliform in both 

 sexes. Coxae of the third pair of pereiopoda almost as deep as 

 those of the preceding pereiopoda, and divided into two equal 

 scales. Posterior pleopoda unibranched. TeLson single. 



The genus Orchestia was confounded for a long time with Talitrus. 

 They were supposed to form one by LatreUle, who founded this genus. 

 They have been placed in the same position by naturalists of more 

 recent celebrity. Mliller places the two genera in one, under the 

 name of Orchestia. Professor Dana, in his great work on Cnistacoa, 

 makes Talitriis a subgenus of Orchestia. 



1. Talitrus Locusta. (Plate I. fig. 1.) B.M. 



Cancer Locusta, Li/oi. Si/st. Nal. ii. 1055, and vol. iii. p. 760, Turtons 



Edit. 

 Cancer (Gammarus) saltator. Montxu/H, Linn. Trans, ix. t. 4. f. 3. 

 Talitrus Locusta, Lntr. Hist. Crust, vi. 229. 



Leach, Linn. Trans, xi. 356; Edinh. Encyc. art. Crustaceology. 

 Talitrus Locusta, Desm. Cons. t. 45. f. 2. 



Itisso, Faune de r Europe 3Ieridio»ale. 



Guerin, Exped. Scient. de Muree, iii. pt. 5. sect. 2. p. 44. 



Brehisson, Cut. des Crust, du Calvados, 1815. 



White, Hist. Brit. Crust, p. 160 ; Cat. Brit. 3£us. 1850. 



Gray, Cat. Brit. Mus. 1847. 



Gosse, Mar. Zool. vol. i. p. 142. 



Spence Bate, Ami. Nat. Hist. Feb. 1857. 

 Talitrus saltator, Edw. Ann. Sc. Nat. xx. 304 ; Hist, des Crust, iii. 



Lucas, Exped. dans FAly^rie. 

 Talitrus litft)ralis, Leach, Edinb. Encyc. art. Crust. 



Second pair of feet feeble, terminating in an imperfect subcheliform 

 hand. The dactylos small, and articulating remotely from the 

 extremity of the propodos. The posterior pair of pleopoda Mn-yj 

 short. Telson rudimentary. 



The cephalon is large and well developed. The Une demonstrating 

 a union between the antennal and mandibular rings is distinct. 

 ITie eyes are very large, and appear near the top of the oephalon^ — 



