studies on marine Ostracnds 129 



In a footnote on the same page the author adds: ,, Since this was written, I have measured 

 the two specimens of ,,lacerta" taken by the ,,R e s e a r c h" in the Faeroe Channel (Proc. 

 Zool. Soc. 1903, p. 122) and now in the British Museum. They were females of 2,0 mm. in length." 



With regard to other species of the family Halocypridae that are dealt with in this work 

 we may note the following: 



In the case of three species, C. elegans G. 0. Sars, C. rotundata G. W. MOller and 

 C. curta J. Lubbock it was impossible for the author to set satisfactory average lengths for the 

 different stages because the curves for these were overlapping, p. 263: ,,the differences in length 

 between the successive stages are so small that measurement to only one place of decimals 

 does not bring out clearly the boundaries between stages . . . ." The average values obtained 

 by approximation agreed very well, however, with Brooks's law. Cf. pp. 263, 274 and 261. 



Conchoecia magna C. Glaus, p. 268, gave less satisfactory results. G. H. Fowler himself 

 tries to explain this by the impurity of the material; no attempt is made to fit this species in 

 with Brooks's law. 



It is true that three stages both of males and females were found of Conchoecia loricata 

 (C. Glaus), p. 267, but the specimens of Stage III were „too few to give satisfactory growth- 

 factors". Only four specimens of this stage were caught, two males and two females. The 

 following average lengths were found: — Females: Stagel, 2,58mm., Stage II 2,0mm., Stage III, 

 1,3 mm. Males: — Stage I, 2,31 mm., Stage II, 1,75 mm.. Stage III, 1,2 mm., These average 

 figures give the following coefficients of growth: — 2,58 : 2,0 = 1,29; 2,0 : 1,3 = 1,54. — 

 2,31 : 1,75 = 1,.32; 1,75 : 1,2 = 1,46. 



With regard to Conchoecia ametra G. W. MULLER p. 259 the individuals that were caught 

 were also too few to give satisfactory growth-factors; three stages of both sexes were found. 



Stated means in mm.: 

 Number of specim. measured: 



From these means the following growth-factors are arrived at: — 3,30 : 2,3 = 1,43; 

 2,3 : 1,42 = 1,6. — 3,10 : 2,16 = 1,43; 2,16 : 1,6 = 1,35. 



Of three species probably only two stages were captured; these species were: Conchoecia 

 inermis (C. Claus), p. 267, C. brachyaskos G. W. MOller p. 259, and C. spinirostris C. Glaus 

 p. 276. 



As to the last-mentioned species G. H. Fowler remarks p. 276: „MCller has des- 

 scribed and figured (Naples Monograph, p. 183, pi. XXXIV, figs. 1, 2, 3, 5) four young stages 

 of this species, of which the two older at least were males; .... Measured without the 

 rostrum, they were 0,33, 0,44, 0,59, 0,79 mm. Now 0,33 x 1,35 == 0,44; 0,44 x 1,35 = 

 0,589 (0,59); 0,589 X 1,35 = 0,79; these are therefore related as in other species." 



Some species were represented by one stage only, viz. Archiconchoecia cucullata 

 (G. S. Brady), p. 279, ConcJwecia pusilla major G. W. Mt'LLER, p. 272, C. kampta G. ^^^ Muller, 

 p. 240 and C. tyloda G. W. MILLER, p. 253. 



17 



Zoolo^. bidrag, Uppsala. Suppl.-Bd. I. ' 



