NO. 2190. ROTATORIA OF LO^ ANOELES, CAL.— MYERS. 475 



Bracliionus patulus MiXiler = BracMonus militaris Elirenbcrg, 3. 

 Brachionus plicatilis MiiWer = Brachionus mulleri Ehrenberg, 8. 

 Brachionus variahilis Hempel, 2, 4. 



This species, originally described from the Illinois River, at Havana, 

 Illinois, was found very abundant. It is commensal on Daplmia 

 longispina (Miiller) and CeriodapTinia longispina (Miiller), which 

 appears to have been unknown to Hempel; nearly every Daphnid 

 carried about a number of these no doubt unwelcome guests, attached 

 to the carapace. Wlien swimming about by the action of its own 

 cilia, Brachionus variabilis behaves very much as other species 

 of this genus, but when deciding to use a Daphnid for conveyance, 

 it attaches itself with astonishmg rapidity, almost jumpmg upon 

 the host. Some of the numerous varieties are illustrated on plate 

 40, figures 1-5. The posterior spmes are found m all lengths and in 

 individuals of all ages; no evidence was observed that would tend 

 to confirm Hempel's suggestion: that only the young have spines, 

 which with advancing age are absorbed. As nothing similar has 

 ever been reported for other species of the genus, it is probably 

 safe to dismiss it as unfounded. 



Brachionus variahilis may be easily recognized by the subquadrate 

 plate projecting over the foot opening; it is therefore evident that 

 the animal figured by Murray m Notes on the Natural History of 

 Bolivia and Peru (p. 26), does not belong to this species, but is no 

 doubt one of the varieties of Brachionus capsulijlorus Pallas, probably 

 the form usually called B. urceolaris. 



Platyias quadricornis (Ehrenberg) = Noteus quadricornis Ehrenberg, 

 3, 4. 



Keratella cochlearis (Gosse) = Anuraea cocJdearis Gosse, 1, 4, 7, 

 9, 12. 



Keratella quadrata (^liiller) = Anuraea aculeata Ehrenberg, normal 

 form, 1, 3, 4, 7, 8, 10; form valga Elirenberg, 1, 2, 3, 4, 7, 9. 



Notholca striata (Miiller), 1, 2, 3, 10. 



Mijtilina mucronata (Miiller) =Salpina mucronata (Miiller), 1, 6. 



Ilytilina ventralis (Ehrenberg) = Salpina ventralis Ehrenberg, 

 normal form and form hrevispina Ehrenberg, 11. 



Euchlanis deflexa Gosse, 1, 3, 5, 6, 7, 10, 11. 



Euchlanis dilatata Ehrenberg, 1, 2, 5, 6, 11. 



Euchlanis lyra Hudson, 3, 10. Not previously recorded from the 

 United States. 



Euchlanis plicata Levander, 11. 



As the figui'e accompanyuig the original description is somewhat 

 diagrammatic, this apparently rare species has been illustrated on 

 plate 41 , figures 1-3. It has not previously been found in the United 

 States. 



Euchlanis pyriformis Gosse, 11. 



Euchlanis triquetra Ehrenberg, 3, 5. 



