174 JULIAN S. HUXLEY. 



PLATE 11. 



Fig. 1. — Large individual at the close of the fii'st trophic stage, with 

 well-formed cup. (Paracarm. x 640.) 



Fig. 2. — Ball end of the same, to show the ball being pushed out 

 through the hole in the cuticle ; the edges of this hole stand out 

 markedly as a rim (cut. rim). ( X 1300.) 



Figs. 3-8. — Ball ends of various Gregarines in different condi- 

 tions. 



Fig. 3. — (Semi-diagi*ammatic). Very slightly extended. 



Secreting tissue very lai'ge, with the granular endoplasm 

 (e,) ending off within it. Outside is a non-granular layer 

 (62), and just l)eneath the cuticle the still paler ectoplasm, 

 extending on the left to touch the ball-v^esicle. (Bor. 

 Carm. X 1875.) 



Fig. 4.— Semi-extended. The secretion of the secreting 

 tissue is fairly dense. The douVjle contour of the hinder 

 part of the Isall is well seen. There seems to be no 

 ectoplasm. (Iron Haim. x 187.5.) 



Fig. 5. — (Semi-diagrammatic.) Completely retracted. Very 

 large cytoplasmic pad (p) with dark grains in it. A 

 large dark granule in the secreting tissue. The ectoplasm 

 extends to touch the ball. (Iron Hann. x 1875.) 



Fig. 6. — Almost extended. The secreted fluid has here a wide- 

 meshed structui-e. The thick body-cuticle ends abruptly 

 where it touches the ball, which possesses only a thin 

 cuticle. Cuticular striae are seen on the under surface. 

 No well- differentiated ectoplasm. (Iron Haem. x 1875.) 

 Figs. 7 and 8. — (Semi-diagrammatic.) Completely extruded. 



In fig. 7 the neck of the ball is well seen, also the more delicate 

 nature of the ball's cuticle. No cytoplasmic i^ad is visible. 



In fig. 8 the ball is directed slightly upwards. The cuticle is 

 distended round the secreted fluid, showing that this is 

 under pressure. (Paracarm., fig. 7 X 1300 ; fig. 8 X 1875.) 



Fig. 9. — Section (5 n) through the point of junction of an associated 

 couple in the first trophic phase. The cytoplasm of the ball individual 

 (A) is denser than that of the other (b). (M. B. E. x 1300.) 



Fig. 10. — Section (5 fi) through the jsoint of attachment of a mobile 

 Ganymedes to a ceU of the host's gvit. The cuticular stria? are well 

 seen. The ball is thrust into the host-cell, and contains a fluid that is 

 not clear, the reticular structure being probably due to the coagulation 

 of absorbed food. There is an open passage thi-ough the neck into a 



