cxlvi On the Affinities of the Pulicites. 



The female is more than double the size of the male, and frequently 

 attacks her prey while the act of coition is still in progress, and, if 

 disturbed, leaping with her customary agility, totally unimpeded by 

 the male, who retains his position with admirable dexterity and sang 

 froid. The female usually lays eight or ten eggs: these are very large 

 in proportion to the size of the insect, perfectly white and oval, much 

 resembling a pigeon's egg in miniature. I have often watched the 

 act of oviposition : it may constantly be observed in hot weather, 

 when a dog infested by fleas is lying asleep ; the fleas then come to 

 the extremity of the hairs, and drop their eggs slowly and at intervals, 

 but quite at random. The eggs appear to me to be perfectly without 

 any viscid covering, and hence do not adhere to the hairs, but gene- 

 rally, after passing amongst them, fall to the ground ; but this is not 

 the experience of prior observers. Thus, Baker* says that fleas " de- 

 posit their eggs at the roots of the hairs of cats, dogs, and other ani- 

 mals, sticking them fast thereto by a kind of glutinous moisture." The 

 same statement has been made by older writers, and therefore I am led 

 to believe that a difference of economy may obtain among the species ; 

 I am able to speak positively only as to a species which infests the 

 dog, and this, as before stated, I have carefully observed in the act of 

 oviposition. This suggestion of the existence of a discrepancy in the 

 character of the egg in different species, is rendered probable by the 

 fact that very excellent observers have described a difference in the 

 character of the larva. Thus DeGeer found those which he examined 

 to be without eyes ; while Roesel found that they possessed those or- 

 gans very conspicuously. DeGeer states that the segments of the 

 body are pilose, and Baker, that they are thinly covered with long 

 hairs ; whereas most authors have either described them as perfectly 

 naked, or left that fact to be inferred. I have never seen the larvae 

 alive, but in one mounted as a microscopic object, I found that each 

 segment emitted a few very minute hairs at right angles with the me- 

 sial line. Roesel himself points out a third discrepancy which came 

 under his own notice : some of the larvae which he procured assumed 

 the pupa state without any covering, while others, as we shall find to 

 be the normal economy, spun delicate silken cocoons, and in them 

 became pupae. 



The larvae are long, apod, vermiform maggots, composed of thirteen 

 very distinct segments, all of them nearly equal in breadth, but the 

 first or head rather longer than the others, and somewhat attenuated 



* Microscope, i. 193. 



