Contributions to the Crustacean Fauna of South Africa. 211 



absolutely characteristic of his genus. He is also equally positive 

 that the 4 species which he assigns to it have only 3 pairs of 

 marsupial plates in the $ . But the present species has 4 pairs 

 distinct both in the ovigerous and the young females. 



It would seem that this character by itself is not enough to delimit 

 the genera of Astacillidae ; for in Astacilla it is stated that there is 

 only 1 pair, attached to the 4th segment (Stebbing, 1893, Sars, 1897, 

 Eichardson, 1905), while in 1910 Eichardson corrects her previous 

 statement and says there are 2 pairs in A. granulata, caeca and 

 dilatata; and in 1911 Koehler maintains that A. granulata, 

 longicornis, deshayesii and his own mediterranean have 3 pairs. 



ARCTUROPSIS HIRSUTUS, var. SUBGLABER. 



Very similar to the female of A. hirsutus, differing only in the 

 following points. 



Body less setose. Head with only two tubercles. Peraeon 

 segments 1-3 and 5-7 without medio-dorsal tubercles, the side-plates 

 only being tubercular. Fourth segment with an anterior pair of 

 bosses and a posterior pair of tubercles, lateral tubercles not very 

 prominent, postero-lateral margin not much expanded, not 

 denticulate. 



There are four pairs of marsupial plates, of which the fourth has 

 a row of 4 inconspicuous tubercles below the hinge-line. 



Uropods, concealed ramus bears 3 long apical spines and 1 

 short one. 



The second antennae are incomplete. 



Length : 17 mm. 



Colour : In spirit, whitish. 



Locality : St. Helena Bay (Paternoster Point SE. f S. distant 

 9 miles). 80 fathoms. 1 ? with ova. s.s. " Pieter Faure." 7/3/02. 

 (S.A.M. No. A52.) 



I am unwilling to make this a new species in the absence of more 

 material, though the distinguishing characters seem to have more 

 than varietal value. The smaller size and thicker coating of setae 

 of A. hirsutus may possibly be due to the warmer water of Table 

 Bay. As noted above, the specimen of A. hirsutus from False Bay 

 (i.e. from the warm Agulhas current) is smaller and more strongly 

 setose than those specimens from Table Bay. These three forms 

 therefore constitute a series, with a rather wide gap between the 

 Table Bay form and the St. Helena Bay form. 



