POINTS OF THE ANATOMY OF POLYXENUS LAGURUS. 10] 
the internal surface of the deutomale in the same position as 
those of Julus and other Chilognaths. I have not thought it 
necessary to give a figure. 
The Nerve-cord. 
The nerve-cord shows a greater resemblance to that of the 
larval Julus and also of Chilopods than does the nerve-cord of 
any other Chilognath with which I am acquainted. Between 
the ganglia the fibrous part of the ventral nervous system is 
divided into two distinct cords as shown in figs. 5, 6, and 12. 
The Internal Generative Organs. 
In both male and female the generative organ has the form 
of a long tube, which communicates with the exterior by two 
short oviducts or vasa deferentia. The female organ (fig. 6) 
consists of a long tube, formed of a single layer of cellular 
membrane, and containing the spongy connective tissue (or 
stroma) within which the ova are produced. Some of the 
cells of this tissue become ova, while others, indistinguishable 
at an early stage, form the follicles which surround the ova. 
At its anterior end the ovary becomes constricted, as shown 
in fig. 5. Its walls increase in thickness, and are composed of 
two layers, an external and an internal, the latter consisting of 
larger cells. Just at the point of division into the two ovi- 
ducts two large receptacula seminis communicate. They are 
composed of a single layer of cells (fig. 5, vec. sem.), and con- 
tain spermatozoa, as shown in the figure. 
The male generative organ also consists of a tube, the 
testis, which divides anteriorly into two vasa deferentia. The 
walls of the testis are formed by a single layer of cells, and 
within it is a mass of spongy connective tissue from the cells 
of which the sperm-cells and the follicles arise. The sper- 
matozoa originate by a sperm morula (fig. 7), and the morula 
is surrounded by a follicle which may perhaps serve to secrete 
the covering of the spermatophores which are formed inside 
the follicles. The spermatozoa are long and thread-like, re- 
sembling those of Lithobius and Scolopendra. 
