472 GEOLOGICAL SUEVEY OF THE TERRITOEIES. 



strong evaporation after continued drouglit, the salt water tlien rapidly 

 reaching a high concentration. 



I have yet to add a few words on the geographical position of the lake 

 and the salt-water ditches iidiabited by Artemia salina. 



Tvro great salt lakes, the Hadschibei and the Kujalnitzkj^, are situated 

 about 7 or 9 versts from Odessa towards Mkolajeft". These two lakes 

 (Russian, limaue) were formerly two broad river entrances and ocean 

 bays, into which two rivers formerly poured. 



At present these two small draining rivers no more deserve their 

 names. The " liraanes " were subsequently cut oft* from the sea by broad 

 stretches of sand, the Peresippe, and vv-ere transformed into salt lakes. 



Only in the lower part of the Kujalniker-Limane, separated by an 

 artilicial embankment from the upper part for the purpose of obtaining 

 salt, is the salt deposited. 



The Hadschibei-Limane showed with my areometer 5° B. as the low- 

 est and 12° B. as the highest concentration. 



The salt-water ditches are distributed over the saline soil in the neigh- 

 borhood of the lake, situated between the lakes and the seashore along 

 the Peresippe to near the city of Odessa. 



In the various ditches occurs salt Avater of various densities from 

 nearly fresh water up to water of 5° Beaume. 



Only the more salty ditches of 4° to 5° B. are inhabited by a (ziem- 

 lich ausgebildet) developed form of Artemia salina, often sissociated with 

 BrancMpus spinosus. In less saline ditches occurs Branchipus ferox and 

 BrancMpus medius. 



Similar results, as regards the evolution of the form, I have also 

 obtained from Daplinia, Cyclops, and Oanthocamptus, and I promise to 

 soon publish these investigations. 



Eemarks. — 1. I have especially endeavored in the above writings to 

 draw attention to the fact that in domesticating Artemia salina in 

 gradually diluted salt water, after several generations and at a pro- 

 gressive development, I obtained a form presenting the most important 

 morphological characters of the genus BrancMpus, so that such a form 

 was at one time regarded by me as a new species of Braiichipus. 



The principal generic characters of Branchipus I regard as the nine 

 apodous postabdominal segments. 



Although we obtain in progressively' domesticating Artemim the 

 characters of the genus BrancMpus, and although,- also, the other char- 

 acters change in the direction toward Branchipus, such an artificially 

 domesticated Artemia, for many reasons and marks of distinction, can 

 only be considered as a lower term of a Branchipus, representing, con- 

 sequently, a transitory form from Artemia toward Branchipus^ and an 

 intermediate form between these two genera. Such a form can also be 

 looked at as n prototy])e or radical type of these two genera. 



2. An im])ortant circumstance is that in those Branchipits observed 

 by me, a few bristles are distributed in a circle around each post- 

 abdominal segment jnst before the articulation, and that in Artemia 

 such bristles occur also in a circle at a little above the middle of the 

 last postabdominal segment. I mentioned above that in Branchipus 

 each such bristle arises out of the middle of a complex of dentate 

 spines, which are of very large size in the male of Branchipus spinosus. 



I find it necessary to add that I found such dentate spines in both 

 sexes of the species of BrancMpus examined by me only on the ventral 

 side of the postabdominal segment just before the articulation, at which 

 location they could be plainly seen. It is well known that in the male 



