PACKARD.] TRANSFORMATION OF ARTEMIA. 507 
milhausentt of the authors (exclusive of their mistakes), and likewise oc- 
curred in it at the same time specimens of the transitory form toward 
A. salina Milne-Edw., whose specimens here were in various degrees of 
degeneration in the direction of Ariemia milhausenti. They were all 
such specimens as those found by me at the end of summer, 1873, 
and middle of summer, 1874, in the Kujalnitzki Lake, near Odessa, that 
is to say, partly complete, partly not fully changed, specimens in form, 
known under the name of Artemia milhausenit. The circumstance that in 
the very saline Sakki Lake, there still occurred also in the middle of July 
many specimens of the transitional form between A. salina and A. mitl- 
hausenii, is explained by the fact that the preceding winter in the Krimea 
was very snowy, that the water in the salt lake in spring became very 
diluted, and that the specimens and generations of Artemia salina had 
to change rapidly in one summer, therefore many specimens did not 
succeed in fully transforming in this one summer. (Only at very gradual . 
increase of the concentration of the salt water have the following genera- 
tions of Artemia salina in all their specimens the form of Artemia mitl- 
hausenti, as observed by me in the course of several years in the Kujal- 
nitzii salt lake near Odessa.) After several days of great drought and 
increase in the amount of the deposited salt in the Sakki Lake, [ could 
not find a single individual of Artemia. I have to state that the speci- 
mens of Artemia in this lake belong to those two races of Artemia sa- 
lina, which live in the neighborhood of Odessa in the Kujalnitzki salt 
lake. The smaller individuals of this much distributed species answer 
to Artemia salina, changed in the known manner, but the larger indi- 
viduals answer to variety a. of Artemia salina changed in the same di- 
rection. , 
It would here be important to know what is really wanting in the 
degraded generations of Artemia salina, in order to possess all the char- 
acters of Artemia milhauseniti Autorum. 
Contrary to the diagnosis of this species (A. milhawsenii of Milne- 
Edwards), we in our generations notice but the one difference, that on 
the female claspers of our individuals toward the middle is found a 
“small protuberance or broadening, Milne-Edwards not mentioning this 
(of course in the females, as the males were yet unknown at that time). 
These words of Milne-fdwards do not correspond with Rathke’s state- 
ments, who described this species under the name of his Artemia salina. 
We see from Rathke’s drawing and description that the second antenn 
of the female of this species has two broadenings divided by a trans- 
verse ring, which the author regards as the two first joints, whereby a 
broadening occurs near the base, another one in the middle of the an- 
tenna, which answers the same as similar broadenings in our female 
specimens with the characters of this species. Im comparing Artemia 
milhausenti with A. salina we must observe that in Milne-Edwards’s diag- 
noses (Histoire naturelle des crustacées, Vol. III) the second antennz 
of the males of A. salina, and the second antenne of the females of 
A. milhausenii, of which latter the males were yet uaknown, have 
been described, as already stated above. For these determinations in 
both diagnoses (cornes céphaliques) Milne-Edwards omitted to give the 
necessary explanation. 
Opposed to this the description of Rathke gives the following differ- 
ence: He says that in this species the upper antenne are four-jointed, 
whichis very doubtful, since in the forms of this genus and in Branchipus 
the upper antenne& are not jointed, but we only observe after a number 
of subsections similar to faint transverse rings, which should not be 
