REPORT ON THE AMPHIPODA. 1507 



" Body only moderately broad, laterally compressed, Gammarid-like, with powerfully 

 developed, semi-flexing pleon. Eostra] point very short and scarcely noticeable. Hinder 

 pair of antennae present in the female. Plates of the maxilla? powerfully developed. 

 Branchial vesicles with lateral accessory compartments. The laminar first joint in the 

 third and fourth peraeopods only moderately extensive and not completely covering the 

 breast." 



Bovallius includes in the family, together with the three other genera, the genus 

 Amphipronoe, Spence Bate, about the validity of which Claus is doubtful. He gives in 

 1887 the following definition : — 



" Head large, not deeper than the body, a little produced anteriorly. Eyes large, 

 occupying the whole sides of the head. First pair of antennae fixed at the under-side of 

 the head ; first joint of flagellum tumid, the rest of flagellum subterminal. The second 

 pair fixed at the under-side of the head, angulated (Pronoe) or angularly folded. 

 Mandibles with palp. Femora of the fifth and sixth pairs of pereiopoda [first joint of 

 Third and Fourth Peraeopods] broad but not transformed. Seventh pair [Fifth 

 Peraeopods] reduced." 



It is a question of terminology whether the first joint of the third and fourth 

 peraeopods should be said to be "transformed" in the Typhidse and "not transformed" 

 in the Pronoidae ; the general character is the same in both, though there are differences 

 of proportion. 



Genus Pronoe, Guerin, 1836. 



1836. Pronoe, Guerin, Magasin de Zoologie, Ann. 6, Classe vii. p. 6. 



1838. „ Milne-Edwards, Hist Nat. des Anini. sans vertebres, t. v. 



1840. „ Lucas, Hist. Nat. des Crust., Arachn. et Myriap., p. 239. 



1840. „ Milne-Edwards, Hist. Nat. des Crust., t. iii. p. 98. 

 1852. 1 „ Dana, Amer. Journ. Sci. and Arts, ser. 2, vol. xiv. No. 41. 



1852. „ Dana, U.S. Explor. Exped., vol. xiii. pt. ii. pp. 1009, 1015, 1443. 



1862. Pronoe, Spence Bate, Brit. Mus. Catal. Amph. Crust., p. 336. 



1879. „ Claus, Die Gattungen und Arten der Platysceliden, p. 23. 



1886. „ Gerstaecker, Broun's Klassen und Ordmmgen, Bd. v. Abth. ii. p. 484. 



1887. „ Bovallius, Systematical List of AtnpL Hyper., Bihang till K. Svensk. Vetensk.- 



Akad. Handl., Bd. 11, No. 16, p. 40. 

 1887. „ Claus, Die Platysceliden, p. 48. 



For the original definition of the genus, see 'Note on Guerin, 1836 (p. 165). To 

 distinguish it from Eupronoe and Parapronoe, Claus gives the characters, " Both pairs 

 of gnathopods simple. Front antennae of the male with two-jointed flagellum, hinder 

 antennae short, only once or twice folded" (see p. 492). 



Claus' fuller definition of this genus is to the following effect : — 



1 It should be observed that Pronoe brunnea, the only species referred by Dana to this genus, is now transferred to 

 Eupronoe, Claus. 



