HOW COCCIDIA MULTIPLY 123 



food is scarce and the space small, as few as four 

 may be produced. They are not arranged haphazard 

 within the body of the parent parasite, now known 

 as the dividing or splitting form the schizont, but 

 gradually pass outwards to the edge, where they 

 become arranged like beads on a girdle, at the 

 circumference (Figs. 27, sch. ; 28, E). Some of the 

 nuclear substance of each portion concentrates to 

 form a more compact part of the daughter nucleus, 

 and little by little the greater part of the protoplasm 

 collects around these daughter nuclei (Fig. 28, F). 

 The result then resembles that seen in an orange, 

 all the daughter parasites (technically termed mero- 

 zoites) being arranged like the segments of the orange 

 (Figs. 27, mz.; 28, F, G). The daughter forms 

 remain together for a short time, but finally separate. 

 Each is a small, wormlike organism, strongly resem- 

 bling the sporozoite, though it is somewhat stouter, 

 and possesses a more marked nucleus than that 

 of the primary infecting germ. The merozoites 

 (Fig. 28, H), when they have reached the surface 

 of the gut, penetrate new host cells in the same way 

 as the sporozoites did, grow, and finally destroy their 

 host cells, and ultimately propagate by division again. 

 Progressive destruction of the lining of the gut thus 

 ensues, and when the parasites reach the blind guts, 

 or caeca, which are very long in the grouse, and 

 attack their lining membrane, the malady becomes 

 much more acute. In fact, birds may recover from 

 coccidiosis in the first part of the gut the duo- 

 denum and then succumb to an attack in the caeca. 

 But multiplication of numbers within the one host 



