PARASITES OP ANIMALS. 329 



the entrance of air. The strongyli accumulate in hundreds 

 in inextricable pellets which the air cannot traverse. Thus 

 these lobules appear to be hepatized." 



" The strongyli fill the bronchia of the calves' lungs during 

 the first year, but they do not long obstruct them ; they die 

 and are eliminated at the end of a season." 



" This is the mode of reproduction of these worms : The 

 females, twice as large as the males, have a long resistant ovi- 

 duct, sinuous and folded upon itself, containing, from its 

 depth to its terminal orifice, eggs in all phases of incubation. 

 At first they are scarcely recognizable ; afterwards are others 

 of which the yolk is divided into 2, 4, 8, or 16 spheres, and 

 whose surfaces are irregular, like that of a raspberry ; fur- 

 ther on, the eggs contain a curved immovable embryo ; at 

 last an embryo in the form of the figure 8, in a loop, or in a 

 spiral, lilce the Trichina in its muscular cyst." 



" It is not necessary that the female should remain alive 

 in order to the laying of the eggs ; even when she dies the 

 expulsion of her progeny is assured. If she lays them in the 

 bronchia, the young ones are developed or expelled. If her 

 progeny must be preserved for a more propitious season, or 

 for another age of the animals which harbors them, she en- 

 closes herself in a tubercle in one of the air sacs, afterwards 

 dies and is transformed into a veritable bag of eggs, destined 

 to furnish, insensibly and for a long period, the contingent 

 which the living worm would have been able, in other cir- 

 cumstances, to render at one laying." 



" The two habitats of these worms thus coincide each with 

 one period of their life and' with certain circumstances of their 

 reproduction. In the cyst they hatch successively with a cer- 

 tain slowness, remain small, asexual, and live surrounded 

 by the debris of their mother. Later, they develop in the 

 bronchia, become sexual, adult, copulate, and prepare, it may 

 be, for emigration externally, it may for a new (internal^ re- 

 production in the lungs, during which they constitute numer- 

 ous reserves for all the period of the life of the mammifer, as 

 is a possible case, not for the calf, but for the sheep." 



" Out of the body of their host the life of these worms in water 



