Marshall — A. Parasitic Ostracod. 
127 
Anteriorly each longitudinal strand articulates with pieces 
which support the antennae and the mouth parts while posteri¬ 
orly they are connected by a loop to which articulate the, sup¬ 
porting pieces of the copulatory organ. This loop in females 
has the position as; given in fig. 8, but in the males is; more dor- 
sally directed and has articulated to it the connecting pieces of 
the copulatory apparatus. In young specimens all the support¬ 
ing strands are almost colorless and very fragile, becoming 
stronger with the growth of the individual. 
Alimentary tract :—The opening of the alimentary tract is 
small being in part closed by the sensory setae projecting from 
the upper and lower lips,, PI. XI, fig. 9. The cavity soon en¬ 
larges toi form the atrium in which the masticatory teeth of the 
mandibles meet. Poliowing the atrium the passage, beginning 
of the oesophagus, becomes much smaller the decrease in size 
being due to a large outfolding of the dorsal wall. Back of 
this growth there is a gradual increase in the width of the oe¬ 
sophagus until it passes into the crop. 
The crop projects into the stomach and shows in longitud¬ 
inal section a marked difference between its dorsal and ventral 
walls. The dorsal wall is much the thicker and has on its sur¬ 
face a chitinous lining covered with short rods. It shows, from 
a depression seen on its anterior wall, that it is, formed by an 
outfolding of the wall between the oesophagus and stomach. 
The wall of the ventral part is also lined with chitin which ends 
in a rod projecting back and beyond the cells. The ventral wall 
is without the bristles or rods described in many other Ostrar 
cods. Zenker (19). Claus (3). 
The stomach, the largest part of the alimentary tract, has, its 
two ends, nearly similar, the anterior end being slightly broader 
due to the presence of the crop,. The cellular structure of the 
crop and stomach is very similar, the cells of the former being 
somewhat smaller and not showing the cell boundaries, dis¬ 
tinctly The wall of the stomach is composed of a layer of cells, 
PL XII, figs. 15 and 16, which in some places, appear cubical, 
in other parts the width is somewhat greater than the height. 
The tissue at the base of the cells, is so thin that no differentia¬ 
tion could be distinguished, while their free ends were often 
