MIT. 7 CESTODE PARASITES OF BIRDS LINTON 29 



nal receptacle. The ovary is small, lobed, and is symmetrically 

 placed with respect to the median line, on the ventral side of the 

 proglottis. The vitelline gland is small, situated at the median line, 

 dorsal to the posterior border of the ovary, and ventral to the shell 

 gland. 



The uterus in ripe proglottides occupies practically all of the 

 medullary space inside the layer of longitudinal muscles. In one 

 series of transverse sections the ova were aggregated in the lateral 

 regions (fig. 83). 



The longitudinal muscles are represented by two layers, an outer 

 of smaller, and an inner of larger bundles. These were not studied 

 in detail, but in one section the larger bundles were found to contain 

 from 20 to 40 fibers, and the smaller from 10 to 20. In transverse 

 sections these bundles of fibers are usually oblong-elliptical in out- 

 line with the longer diameter radial. 



The marginal excretory vessels lie close together, the ventral 

 being much larger than the dorsal. The poral pair lie on the 

 ventral side of the cirrus and vagina. In figure 83 it is seen that 

 the ventral excretory vessel persists in the ripe proglottis, lying in 

 the lumen of the uterus. Diameter of ova about 0.027 by 0.021 mm. 



RECORD OF COLLECTIONS 



From Butondes virescens: 



(U.S.N.M., Helm. Coll. 7872.) 

 1887, July 29.— One, length 102 mm., breadth 2.2. 

 1913, July 9. — Two, each about 100 mm., maximum breadth 



5 mm. 

 1913, July 12. — One, length 125; three fragments. 



1916, July 20. — One, length 85 mm., in intestine of one of three 

 herons. 



HYMENOLEPIS CORONULA (Dujardin) 

 Figures 89-93 



Scolex. — Short, bluntly rounded in front, with suckers directed 

 forward (in scoleces with rostellum retracted); rostellum short; 

 hooks about 20, in a single circle, strongly recurved, length about 

 0.01 mm. Diameter of scolex 0.15, of suckers 0.07, of circle of 

 hooks 0.03. 



Strobile. — Neck at first usually as broad, or broader than the 

 scolex, narrowing slightly a short distance behind the scolex; first 

 segments about 0.5 mm. from the scolex. The ^proglottides are very 

 short and crowded even in the longer strobiles. The last proglottis 

 in the smaller mounted strobiles is narrower and longer than the 



