408 WILLIAM A. HASWELL. 



Its cells, several hundred in number, are arranged in a radiat- 

 ing manner round tlie oviduct, their narrow inner extremities 

 evidently acting as ducts by Avliich the secretion is dis- 

 charged. Their nuclei are large, a little less than '005 mm. 

 in diameter. Between the cells are a number of smaller 

 nuclei indicating the presence of a certain amount of inter- 

 cellular tissue. 



The vitelline glands (fig. 3, v.) extend throughout a narrow 

 belt of the lateral regions of the body from the neck to the 

 posterior end. The lobes are spherical or subspherical in 

 shape, and average about "OS mm. in diameter. Each lobe 

 has its slender duct, which joins those of neighbouring lobes 

 to form larger ducts, and these again combine to form the 

 main lateral ducts (fig. 7, v. d.). These converge from both 

 sides towards the middle line, running on the ventral side of 

 the ovary, and finally unite to give rise to an impaired main 

 duct, situated slightly to the right of the middle line. This 

 runs backwards and joins the oviduct as already described. 

 Near its termination it is usually distended with yolk, and this 

 dilated part (figs. 7, 8, and 9, v. r.) ('OS mm. in diameter) 

 might be looked upon as a yolk-receptacle. It is followed by 

 a constricted part with thickened walls (fig. 8, v. r. c.) 

 through which the yolk cells can only pass singly to enter 

 the oviduct. The yolk matter leaves the lobes of the glands 

 in the form of very regular spherical masses "012 mm. in 

 diameter, each of which contains one, or sometimes two, 

 rounded bodies which, as they are capable of being stained, 

 though only slightly, are very liable to be mistaken for 

 nuclei. These bodies will be further referred to in the 

 description of the egg. Meanwhile it is of importance to 

 emphasise the fact that they are not nuclei, and that the 

 vitelline masses in which they are lodged are not cells. ^ 



The wall of the vitelline ducts consists of fibrillated proto- 

 plasmic material with Tiuclei at intervals. In the main duct 



' This is contrary to what is usually slated of Ccslodcs in general. J>raiin, 

 for example, states : " Die Ansicht Moniez's dass die Dotterzellen keine 

 cchleu sondern nur Scliciiizellcn scien enlbelirl jedcr Begriindung (5, p.HGS). 



