PROCKEDIXlJ.S. 1!)!."). 89 



in any definite portion of the animal. In the case of the cat the lar\ae 

 may have been swallowed when it was feeding on a squirrel. The onl_\' 

 availaljle reference of a similar kind is quoted b}' Washburn, where, he 

 says: "Unidentified bots, possibly belonging to this genus (Cuterebra), 

 ha\e been taken from beneath the jaws of kittens." 



.\ccording to Townsend the larwie i:if C. fontinella, wliirli he ftiund 

 m rabbits, showed no selective faculty for an}- special part of the body. 

 The [jositions he mentions are: The dorsal, pectoral and the \entral 

 regions. 



It may be well here to make a brief comparison between the eggs of 

 the different Oestridae, of which 1 have descriptions. 



Hypoderma bovis and H. lineatum have smooth eggs, attached to 

 the hairs by a ])edicel, and show no trace of operculum. The egg splits 

 ojjen to alli.iw the emei'gence of the lar\a. 



The egg of Oedemagena tarandi, the reindeer Warble-fly, has a 

 modified operculum in the shape of a thin flap, along the edge of which 

 the egg splits open, it is attached b_\- a pedicel. According to Carpen- 

 ter's figures, the egg of O. tarandi, apart from the (.i])ening flap, closel}' 

 resembles that of Hypoderma. 



The egg of Gastrophilus equi is somewhat cur\ed. probabh" owing 

 to the groove by which it is attached to the hair, which runs along the 

 under side for about half its length. This groove must occupy space in- 

 side the egg, hence the corresponding bulge on the other side, to give 

 room for the lar\a. It has a well-defined operculum, differently marked 

 from the rest of the egg, 



Cuterebra fontinella — This closely resembles the egg of G. equi in 

 shape and in possessing an operculum and a similarly shaped groove. 

 The groove, however, is proportionately longer. The main difference 

 is in the surface of the egg case, which is rough but not lined as in 

 G. equi, there is no different marking on the operculum. 



.According to the conformation ni the egg. it is thus ])ossil)le lo 

 separate the species mentioned above. .\s C. fontinella is close to G. equi, 

 it would be reasonable to suppose, then, that in their manner of entrance 

 at least, the lar\ae of Cuterebra resemble those of Gastrophilus; and 

 the fact that rodents are continually licking themselves adds strength to 

 the hypothesis. 



According to Townsend and i'>au the host of C. fontinella i> Lepus 

 artemisia, Bachman (Cottontails). In this part of liritish Columbia rali- 

 biis are not plentifid and we ha\e no records of an}- having been found 

 parasitized b}- this grul). It w-ould a])])ear that there is a possibility of 

 C. fontinella ha\ing another host, two females were collected by Mr, 

 R. S. Sherman on Savary Island, \\-hich is a small island in the Straits of 

 (k-orgia where no rabbits exist. llo\\e\er, mice are quite common on 



