STEBBING— ISOPODA 99 



size, its rather more slender legs, its differently shaped masculine appendix to the second 

 pleopods of the male, and above all by the possession of an acuminate horn on the base of 

 the frontal lamina. 



The specimens from the Seychelles agree closely in size with Hansen's measurements, 

 which are 4*3 mm. for the male, and 4'8 mm. for the female, though I cannot pretend to 

 the same nicety in determining the fractions of a millimetre. Also, they have the 

 masculine appendix, not incurved as in C. parva, but quite straight, ending acutely much 

 (in one case very much) beyond the other part of the ramus. But the hinder perasopods 

 do not show the special slenderness of the second joint which Hansen figures, and I 

 cannot perceive the recpiired horn on the frontal lamina of either of the two males 

 dissected. 



Localities. Praslin Reef and Coetivy. A female specimen, 5 mm. long, from Diego 

 Garcia, carried numerous young ones in an advanced stage of development. Its first 

 antennas have a nine-jointed flagellum, and its second one of twenty-two joints. 



Fam. Corallanidse. 



1904. Corallanidse, Stebbing, Gardiner's Fauna Maldive and Laccadive Arch., 



vol. ii., pt. 3, p. 703. 



Geu. ALGIRONA, Hansen. 



1890. Alcirona, Hansen, Vid. Selsk. Skr., ser. 6, vol. v., p. 285. 



12. Alcirona maldivensis, Stebbing. 



1904. Alcirona maldivensis, Stebbing, Gardiner's Fauna Maldive and Laccadive 

 Arch., vol. ii., pt. 3, p. 708, pi. 51b. 



The present specimen is larger but proportionally narrower than that originally 

 described. It is likewise a female with young, which, as in the other case, are far 

 advanced. 



Length 7 "5 mm. Breadth 3 mm. 



Locality. Cargados Carajos, where the " Sealark " obtained it from a depth of 

 30 fathoms. 



Fam. Argathonidse. 



1905. Argathonidaa, Stebbing, Herdman's Pearl Fish., Suppl. Rep. 23, p. 1G. 



In the single species for which this family was founded the fourth and fifth joints of 

 the maxillipeds are fused into one. Another species has now come to light, in which the 

 distinctness of these two joints is clearly manifest. This might be regarded as an 

 important generic difference, were it supported by any other character of equal weight. 

 But that is not the case. In all other resj)ects features than can fairly be allowed generic 

 value appear to be the same for both species. 



Gen. ARGATHONA, Stebbing. 

 1905. Argathona, Stebbing, Herdman's Pearl Fish., Suppl. Rep. 23, p. 17. 

 The statement that the maxillipeds are six-jointed through fusion of the fourth and 

 fifth joints must be excluded from the definition alike of the family and the genus, as 



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