PACKARD.] PHYLLOPODS OF NORTH AMERICA. 335 
This genus stands in simplicity of structure next above Artemia, being 
related to it by its short cercopoda or caudal appendages, and the simple 
male claspers, with the knob-like projection at the base of each. It is 
less complicated than in Branchipus, and in his valuable paper on this 
group I hardly understand why Professor Verrill should have interposed 
Branchipus, his Hubranchipus, Streptocephalus, and Chirocephalus between 
Artemia and the present genus, as the genera in the order we place them 
in this essay present successive degrees of complexity from Artemia to 
Chirocephalus and Thamnocephalus. The Southern European Branchi- 
pus spinosus Nordman, from a salt lake at Odessa, appears to us, on ex- 
amination of a number of specimens received from Professor Siebold, to 
belong to this genus, contrary to Verrill’s opinion, who referred it to bis 
genus Hubranchipus. In this species the knob-like processes of the 
male claspers are present; the male claspers also are much as in B. 
coloradensis, but much slenderer ; the caudal appendages are short and 
small, as in our American species of Branchinecta, but the ovisaes are 
rather shorter than in any American and Arctic species, though still 
longer thanin Branchipus. The genus is certainly a good one, and easily 
distinguishable. It is especially interesting to indicate the close affin- 
ities of this genus to Artemia, for it is Branchinecta ferox (Fischer sp.) 
which Schmankevitch found to transform by artificial means into Arte- 
mnia, and the characters ot Branchinecta are such as we might believe a 
well-fed Artemia subjected also to water of suitable temperature and 
freshness might suddenly acquire. The fact, however, that the two 
genera may be artificially produced does not militate against the natural- 
ness of the two genera, Artemia and Branchinectes, since we can point 
to three American and Arctic species of Branchinecta which preserve 
their generic identity. 
As suggested by Verrill, Milne-Edwards’ Branchipus ferox (Edwards’ 
Crustaces, ili, 369), from fresh water near Odessa, most probably belongs 
to this genus. Milne-Edwards thus characterizes it: ‘‘Cornes cepha- 
liques sans appendice. prés du céte interne de leur base, pointues au 
bout et sans dent sur le bord externe. Abdomen lisse, Wei ies cau- 
dales longues et étroites.” It has been rediscovered in 1872 in salt 
pools near Odessa by Schmankevitch. Verrill also states He Bran- 
chipus middendorfiana Fischer, of Siberia and Lapland, may be a Bran- 
chinecta, and, judging by Fischer’s figures of the male clasper, the ovisae, 
and the cercopoda, it is without much doubt a genuine Branchinecta. By 
Grube and Dybowski it is regarded as a synonym of B. paludosa. It 
inhabits Siberia, having been collected by Middendorf near the rivers 
Taimyr and Boganida, as also in Lapland near Tri-Ostrowa, while it was 
also collected by the Ural Expedition. Hence the species of the genus 
Branchinecta range from the Arctic regions to Southern Russia in Eu- 
rope, and to the higher portions of the Rocky Mountain plateau of Colo- 
rado in North Ameri ica, aS Well as the plains of Kansas, the genus, with 
the exception of the two species living at Odessa, and B. lindahli, of 
Kansas, being inhabitants of Arctic and Alpine regions. 
Synopsis of the species. 
Male claspers pointed, not turned in, serrated inside of 2d joint; no 
G00 De CR pean Poe SO a ees ee ee ee L. paludosa. 
Male claspers large, end broad and bent in, with no teeth; knob 
EeneaT ritigs. PSE Ulad MON tee le Cad Lesa ol seek, B. coloradensis. 
Male claspers short; caudal appendages very long......... BL. lindahti. 
