THE CANADIAN ENTOMOLOGIST. 27 



indirect descendants, the author has indicated several principal stems (not 

 primitive forms). In respect to the North-stem and the South-stem in the 

 groups occurring in the Holarctic region, he lays down the following 

 hypotheses : 



The two North stems developed, during a colder period, in what is 

 now a warmer region of Africa. Later they separated, the smaller part 

 going southward, seeking the cooler climate, the main body being mean- 

 v»'hile forced farther and farther to the north, returning later (split into 

 North American and Eurasiatic branches) to the south. The home of the 

 two so-called South-stems may be in the warmer part of America. Then 

 follows a phenomenon analogous to the above, with the difference that 

 here two equally great migrations took place, the forerunners of the 

 cuprascens group going northwards, those of the iiivea-ritiemce group 

 southwards. Both reached the Arctic or Antarctic land connections 



• 



The sj)ecies of the elegans-trisignata group are then the posterity of the 

 south-bound Arctic Eurasiatic branch, the hclnisi-duneduiensisscetigera 

 group perhaps coming from the north-bound Antarctic Australasian 

 branch. In spite, however, of these statements, neither the Arctic nor 

 the Antarctic regions have produced indigenous Cicindelee, their influence 

 on the great influxes being only that of paths of* a passing emigration. 

 The true home of all the Cicindela stems is in the tropics or the subtropics. 



NOTES ON T^NIORHYNCHUS SQUAMIGER, COQ. 



BY H. J. QLTAYLE, AMES, IOWA. 



Prof. Smith, of New Jersey, records TcBniorhyiichiis { Culex) squamig€i\ 

 Coq., as being a strictly fresh-water form in that State, and it will be 

 interesting to know that so far as my experience goes during the past 

 season, it is exclusively a salt-marsh mosquito in the San Francisco Bay 

 region of California. It may be possible that we hav^e two different forms, 

 but in a quantity of material which I have just examined they appear to 

 agree in all essential particulars, both as regards larva and adult, with the 

 descriptions given in Prof. Smith's report. There is one character, how- 

 ever, in the larva that is quite at variance, and that is the tracheal gills. 

 In my specimens they are very short, in no case as long as the width of 

 the 9th segment, while in Prof. Smith's report they are given as longer 

 than the length of the segment, for the New Jersey squamiger. At any 

 rate, if they are not the same mosquito, I believe my specimens are the 



Januar}-, 1906. 



