AMPHIPODA STEBBISG. 631 



In Dr. Maj'er's species the three pairs of branchial vesicles 

 from front to rear decrease considerably in size. This is not the 

 case with the new species. Though the first pair is larger than 

 the third, the second is very conspicuously larger than the first, 

 in both sexes. 



The fourth and fifth peraeopods are only rarely found in 

 position. For the sixth joint in the Port Jackson specimens Dr. 

 Mayer describes the clasping spines as consisting of one pair and 

 two that are impaired. In the new species near tlie proximal end 

 there are in both sexes two successive pairs of spines and a single 

 spine near the hinge of the finger. 



This assemblage of differences should sufiice to discriminate the 

 two species. That they should be found in unmixed numbers in 

 apparently close proximity, is of no controversial importance 

 apart from more precise information as to the exact conditions of 

 capture in each case, or, in modern phrase, as to the oecology of 

 the two species. 



The new species has the eyes rounded, very prominent, dark 

 red in spirit. The mouth-otgans are in near agreement with 

 those of Dodecds dongata. In the second gnathopods the fifth 

 joint is as usual short in the female, but long and slender in the 

 male, distinct from the sixth but without separate mobility. 

 The palm of the sixth joint has two emarginations, of which the 

 distal one is the longer, but veiled by a transparent membrane. 



The pleonis in near agreement with that of Dodecas elongata, 

 having in the male at the base a ventral median plate carrying a 

 minute pair of oval pleopods, each ending in aseta.^^ The platt 

 alone is present in the female. The uropo<ls are in agreement 

 with those uf D. elongata, except that the first pair does not so 

 greatly exceed the length of the second. 



Three male specimens measured, respectively, 18-5, 18, 17'5mm. 

 Of the first, the first antenna, witn flagellum broken after the 

 8th joint measured 14 mm., of the second the antenna was only 

 105 mm. long, of the thiid the antenna with flageilum complete 

 was 14 mm. A female specimen, 17 mm. long, had a first 

 antenna 9-5 mm. in length, of which the 19-jointed flagellum 

 measured 4-5 mm. 



Localities. — Port Hacking ; Botany Bay, from depth of .50-52 

 fathoms off Wata Mooli, from 54-59 fathoms. 



Genus ORTHOPROTELLA, Mayer. 



Orlhoprotella, Mayer, Siboga Expeditie, xxxiv., 1903, p. 35. 



Distinguished from Protella {in its latest restriction) chiefly by 

 the pleon of the male, which carries one pair of two-jointed rudi- 



13 See Mayer— i^oc. dt., 1890, p. 126, pi. v., (ig. 7. 



