studies on marine Ostracods 675 



specimens investigated by nic). The differences in the length of the shell and the armature 

 of the e-bristle on the male first antenna are, however, more important. 



In his later works G. W. MtJLLER retains the view that he adopted in his work of 1906 a. 

 In his synoptic work (1912) he thus writes C. secernenda as a synonym of C. bispinosa. 



It is of course exceedingly difficult for me to have any decided views on this question, 

 as I have only been able to investigate a rather small material of these forms. I have prelimi- 

 narily sided with V. VAv'RA. The facts that led me to this decision were, first, the discontinuity 

 of the variation in the length of the shell observed by 6. W. MOller at several localities and, 

 secondly, the fact that in the male investigated by me the e-bristle on the first antenna was 

 armed with about the same number of spines as C. Claus found in the specimens investigated 

 by him. 



Besides the places included in the list of synonyms worked out above C. bispinosa C. 

 Claus is mentioned in the following places: G. S. Brady, 1897, p. 95, P. T. Cle\^, 1905, p. 129 

 and G. W. MtlLLER, 1906 b and 1908. The reasons why I did not include these statements in 

 the list just mentioned are, first, the uncertainty I have just pointed out and, secondly, the fact 

 that there is no verificatory information about them. 



C. bispinosa, P. T. Cleve, 1900 is also without any verificatory information. I have 

 nevertheless included it as a synonym because I have myself investigated the original material 

 of this form; cf. below. 



G. W. MiJLLER (1912) also includes C. Miilleri, Cll. JUDAY. 1906 as a synonym of C. 

 bispinosa. This identification is probably incorrect. Unfortunately, however, the original 

 description of this species is too incomplete and uncertain to permit of any certain decision 

 (length of shell, <S = 2,6 mm., $ = 2,8 mm.). 



C. bispinosa is extremely closely related to C. Haddoni. The only characters that ftelations m o:her 

 distinguish these two species are really, as is shown above, the occurrence of spines on the species. 



posterior dorsal corner of the shell in C. bispinosa and the armature of the e-bristle on the male 

 first antenna. In the latter character the (large) specimens of C. Haddoni investigated by me 

 resembled C. secernenda. Cf., in addition, the female antenna in the two forms. It would 

 perhaps be most convenient to include C. Haddoni as a variety of 

 C. bispinosa. That they are identical, i. e. that the differences mentioned are due to individual 

 variation, seems to me rather improbable, especially because their areas of distribution do not 

 qmte coincide. Thus G. H. FowLER found C. Haddoni in the Bay of Biscay, but not, on the 

 other hand, C. bispinosa, in spite of the not inconsiderable material. V. VAVTiA found C. Haddoni 

 at four stations ,,in vielen Exemplaren", C. secermnda at not less than twenty stations. In 

 addition the two forms were never found together. Cf. also G. W. MUller, 1906 a. It remains, 

 however, a task for future investigators to examine this question in more detail. 



Habitat: — Atlantic Ocean: 



S. A. E., PI. station 30, lat. 29" 52' N., long. 20" 14' W.; at the surface; 7. XI. 1901; 

 temperature, 21",1 C: 1 male juvenis; R. M. S. 259. S. A. E., PI. station 4 b, lat. 25" 51' N.. 

 long. 210 29' W.; at the surface; 9. XL 1901; temperature, 22,50 C: 2 mature females; K. M. 



