How many species may properly be referred to this genus 

 does not appear to have been yet determined by any full and 

 accurate examination, nor hav-e 1 the materials for deciding. 

 In addition to the characters mentioned in the discussion of 

 the family given above, Bate mentions that in his two species 

 of Poitocaris the rostrum is short, not longer than the eye- 

 stalks, that the exopod of the second antennae is short and 

 broad, that the first trunk-legs have a small one-jointed 

 exopod, that the pleopods are broad and foliaceous, and that 

 the outer branch of the uropods has no diaeresis. All these 

 characters belong also to ^^geon cataphr actus. In the latter, 

 and apparently also in the other two species, the longer inner 

 flagellum of the first antennae is except at the distal part 

 greatly widened in the male, but not in the female. 



^GEON CATAPHRACTUS ;Olivi). 



I7Q2. Cancer catapJiractiis^ Olivi, Zoologia adriatica, p. 50^ 



pi. 3, f. I. 

 1816. Egcon loricatus, Risso, Crust, de Nice, p. 100. 

 1826. Egcon loricatns, Risso, Hist. Nat. Europe Merid., vol. 5, 



pi. i,f. 3. 

 1837. Crangon cafapracfus, Milne-Edwards, Hist. Nat Crust., 



vol. 2, p. 343. 

 1839. Crangon catapractus, Milne-Edwards, Regne Animal, 



Ed. illustr., pi. 51, f. 3. 

 1849. Crangon catapractus, Lucas, Expl. Sci, Algerie, Crust,, 



^ P- 39- 

 1862. Crangon cataphractus^ Heller, Crust. Siidl, Europa, 



p. 230, pi. 7, f. 12-15. 

 1869. Crangon caiaphracfus, Nardo, Mem. R. 1st. Veneto, 



vol. 14, p. 237. 

 1 88 1. Crangon [CherapJiiliis] cataphractus, Miers, Ann. Nat. 



Hist., Ser. 5, \'ol. 8, p. 365. 

 1885. Crangon caiapkrachts, Carus, Prodr. Faunae Medi- 



terraneae, p. 482. 

 1890. jEgeon cafaphractiis, Ortmann, Zool. Jahrb., vol. 5, 



part I, p. 535. 

 This species is easily distinguished from the Pontocaris 

 propensalata and Pontocaris pennata of Bate, because of the 

 seven carinae on the carapace, the central one is formed of 

 only four or five teeth, while in those species it is composed 

 of nine teeth, of which the hinder ones are comparatively 

 small. jEgeon veftnatus, unlike the other two, has the fronto- 

 lateral angles of the carapace strongly produced into oblique 

 processes, and yEgeon propcnsalatns has an acute rostrum 

 instead of the emarginate one found in ^geon cataphractus 

 and at least in one specimen oi u^geon pennatus. 



