76 AVIAN CESTODES, 



is shown in Fig.l. The first proglottid is abovit 0017 mm. 

 long, and 018 mm. broad, the ratio being 1 : 10. As the length 

 increases much more rapidly than the breadth, this ratio 

 decreases. In the fourth, the length is 008 and the breadth 

 0-273 mm., the ratio being 1:3-4. In the sixth segment, 

 where a marked increase in length, accompanied by full 

 sexual maturity occurs, the length is 01 30 and the breadth 

 0-283 mm., the ratio being nearly 1:2. In the seventh 

 segment the difference is about equalised, the segment being 

 rounded, the length reaching 0-243 and the breadth 0-291 

 mm., the ratio now being 5:6. The next segment is fre- 

 quently much broader, and slightly shorter, being 0-40 by 

 0-227 mm. It is at this part of the strobila, where egg- 

 formation is actively proceeding, and where the segments 

 themselves seem to be thrown off, as each end of this and 

 succeeding segments (if any) is strongly contracted. Some 

 free proglottids were measured with the following results : — 

 (a) Length 0-390, breadth 0-468 mm. ; (b) length 0-437, 

 breadth 0-65 mm. This seems to indicate, either that there 

 is a very considerable increase in growth after the separation 

 of the ripening segments, or (more probably) that those which 

 are ripe are so feebly connected with the rest of the strobila, 

 that they readily become detached. 



It will be noticed that, in no case, do the posterior edges 

 of the segments project, but that the lateral margins are 

 convex outwardly. 



The genital pores alternate regularly, as a rule, very few 

 exceptions being detected. It is only in the larger pro- 

 glottids that the pores are present. They are located in the 

 anterior third of the lateral margin. There is no genital 

 papilla, even in cases where the cirrus is everted. The 

 genital cloaca is relatively deep and narrow. 



Calcareous corpuscles were not detected, nor was any part 

 of the nervous or excretory system. The longitudinal mus- 

 culature is seen to be well developed, and to consist of a 

 number of powerful bundles which may be traced from one 



