studies oil iiiariin' O.stncoils 567 



l.vvi'lvi". Among these twelve speeies tliere are several ol' which a lairlv abundant material 

 was at the disposal of the investigator, e. g. C spinifera and C elegans. This fact alone should 

 have aroused the atithor's suspicion. 



With icuaid to the eight former species I may point out the foUowing facts: 



('. zetesius: — Only two stages, ,, Stage (?) I" and ,, Stage (?) 11" of this species, which 

 (t. H. F<»\\I.i:1! himself established in the work in question, were found in the material investig- 

 ated by this writer and only females were found of both. The same stages were also found 

 l)y me in material brought home by the ,,M i c h a e 1 S a r s" from the deep sea expedition 

 of l!ll(». Both males and females were found. As I hope to be able to show in a subsequent 

 work on the Ostiacods of this expedition, these two stages represent in all probability 

 the first and the second larval stages of C. macrocheira G. W. MOller.* Because of this G. H. 

 Fouler's assumption that the last-mentioned species is ,, Stage I" of ('. magna C. Claus 

 also collapses. 



C. rotundata: — As is j)ointed out below(ina, noteon C. ro<W7ii/oto), it seems to me extremely 

 probable that this species, as it is at present taken in the literature, is not a unit; it probably 

 consists of two forms very closely related to each other, one of which has a somewhat more 

 elongated shell than the other. This view is supported by the fact, among others, that the 

 geographical distribution of these two forms does not seem to be the same; while both forms 

 are found, for instance, in the Bay of Biscay and in the greater part of the Atlantic, only the 

 more elongated form seems, on the other hand, to occur in the Antarctic. According to G. H. 

 F<)\\iJ*:i;'s presentation the larvae of this species always belong to the short and high type. 

 According to what I have observed myself the larvae of the elongated Antarctic form have 

 about the same elongated type as the mature individuals. Elongated larvae are thus found. 

 It does not seem to me impossible that these also occurred in the material investigated by 

 G. H. FOWLKH but were overlooked on account of their small number; one ought to note the 

 great difference in number between elongated and short mature specimens in this material — 

 the latter were very numerous, the former, on the otliei- hand, very sparse. Finally it is to 

 he noted that G. H. Fowi-l'^l: diil not succeed in ..bringing out clearly the successive stages" 

 ill the measurements taken by him to prove Brooks's law in this species. This fact too 

 seems to indicate! that the material was not pure from a systematic point of view. 



C. spinirostris: — In the case of this species too it seems to me probable that a confusion 

 has taken place between two very closely related forms. For the reasons in support of this 

 view of mine I shall in this coimectioii only refer to what 1 have written })elow, remarks on 

 ('. spinirostris. 



C. Haddoni: — In the material investigated by G. H. Fowler only two mature males 

 of this species were found, both with shells 2,1 mnt. long, and three male larvae, all with shells 



* .\s can be seen rnnii tlii' I'dllowing woj'ij.s G. H. Fowi.iiit liiiiiself had a preseiilinieiil uf the elose lelatioiishiii 

 liel\v<'eii .,C. zctesins" and C. macrocheira; he writes p. 2;')'!: ,,The species oliviously l)eloiigs to the magna gi'oiip. 

 While the slujlJ-fonlour to some extent resembles thai of .,inacrochcira'\ its Iroiital orijan ami the slender longer bristle 

 u! ttie inner joint of antenna II. are very far from tin; magiia-macrorheira lyi)e; nor can it he fitted into the lengths 

 which liave been wnrked (lut for that series. It is remotely possil)le that it may lie a dimorphic parthenogenetie 

 form iif magna, Ijiit )>artlienogenesis has not yet lieen shown to ciiriir in llir I[alo(vpri(hie", 



