18 TAGE SKOGSBERG, A NEW FRESH-WATER OSTRACOD. 
them; the last of these seven bristles is situated at the posterior edge and of the 
same type (sensoria]l?) and size as the corresponding bristle of the male. As to the 
bristles of the end-joint only a very slight difference between the sexes is to be 
noted — the bristle corresponding to the anterior of the three ordinary weak bristles 
of the male — i. e. that which in other genera of this family is often more or less 
claw-like — is in the female somewhat stronger and slightly pectinated. Plumosity 
as in the male. 
Fifth leg: Shows like this leg of the male a close agreement with G. O. SARS”s 
description. The basal portion and the masticatory process have the same number 
of bristles as in the male; the three end-bristles of the endopodit are plumose. 
All the other legs as well as the furca are exactly similar in both sexes. 
The genital lobe as drawn and described by G. O. SARS. 
Remarks. — As will be seen from the above I have, with some reserve, iden- 
tified this species with the form described by G. O. SArEs, 1889, under the name 
Cyprinotus dentato-marginatus (BAIRD), from specimens, raised from dried Australian 
mud. Though several differences exist between the description of G. O. SARS and 
my own with regard both to the shell and to the extremities — differences which a 
comparison of the two descriptions will make clear — this identification may never- 
theless be considered fairly well-established, as the agreement between the two forms 
is striking and the comparative superficiality of G. O. SARS's description evidently 
does not exclude the possibility that mistakes on the part of this author may be 
the real reasons for the differences mentioned. 
The original description of the species, Cypris dentato-marginata W. BAIRD, with 
which G. O. SARS has identified his form, is to be found in the Proceedings of the 
Zoological Society of London, Part XXVII, 1859, p. 233. It is very short, given in 
general terms, and, as it deals only with the shell, is quite insufficient for certainty 
of identification. The drawings, Pl. LXIII, figs. 5, 5 a-—c, showing two somewhat 
different types (figs. 5 and 5 a) of shell, leave us in doubt even as to which may be 
considered the true shape of the valves. 
Here it may be noticed that in the explanation of the plate this species — 
evidently owing to a misprint — is named Cypris marginato-dentata. 
The shell of another form, not mentioned in the text, and in the explanation 
to the plate named Cypris marginato-dentata var., is also reproduced, Pl. LXIII, 
figs. 5d—f. In all probability it does not, however, belong even to a species of the 
subgenus Cyprinotus, as far as we may conelude from the drawings, which are very 
superficial. 
Whether G. O. SArR$'s identification is right or not is a question which cannot 
be settled in the present state of our knowledge, as this author, to judge from his 
words on p. 7, has not made a re-examination of the type-specimen of the species. 
As the shell is not sufficient for a certain identification of a species of this sub- 
genus and as, in fact, differences exist between the two forms, I have not con- 
