130 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 
upon other parts of the apparatus. The Glandular Cells (gl.c) are situated 
at the margin of the alveolus. The chitinous teguments above these in 
the cymbium are pierced by a number of ducts, which eventually serve 
as conduits for the secretions of the cells. 
The Hematodocha is a delicate chitinous saclike organ, of which the 
bottom is inserted into the alveolus, and the superior margin into the 
inferior face of the tegulum. Thus the entire basal part (recep- 
eran taculum seminis), which is situated under the tegulum, is within 
the cavity of the sac. The walls of the hamatodocha are very 
thin and plaited, so that if the sac be full it is able to attain large dimen- 
sions. In its ordinary condition with most spiders it is folded in a spiral 
and situated’ within the alveolus. 
The bottom part, by which the sac is attached to the concavity of the 
alveolus, has a round orifice (orificium heematodoche, or.hem), which 
unites the cavity with the lacuna of the cymbium situated beneath. Mr. 
Wagner says that during fecundation the hematodocha is not filled with 
sperm, as certain observers suppose, but at that moment is filled with 
blood. Its role is to transmit, under pressure of its elastic walls, the blood 
which has come to the lacuna into the cavity of the receptaculum seminis, 
through certain fine ducts (meati sanguinis), by which the cavity of the 
receptaculum is united with the cavity of the sac. It follows that the 
function of the hematodocha is that by its means the blood takes part in 
fecundation by penetrating, although in small quantity, along with the 
sperm into the genital cavity of the female. 
Upon the superior part of the copulatory apparatus, and in part within 
the cavity of the hematodocha under the tegulum, is situated a tube with 
thick, chitinous walls, which in different species of spiders differs 
Recepta- in shape, length, and position. This is the receptaculum seminis 
culum r . Pies 
Seminis. (ree-sem). The extremity of that part situated under the tegulum, 
the basal part of the tube, is always closed. The opposite end ter- 
minates in an orifice at the summit of the embolus (emb). At the moment 
of fecundation the receptaculum is filled with sperm. Its role is as follows: 
Shortly after the moult it is filled with sperm, which the male has forced 
from his genital orifice upon a woyen thread or tissue previously prepared. 
He plunges his palp into his drop of sperm, which, by the law of capil- 
larity, mounts into the receptaculum through the orifice (or) of the embolus, 
the only organ of the copulatory apparatus that receives and conseryes the 
‘sperm. The sperm can only be discharged by the orifice of the embolus 
through which it entered. The slender ducts (meati sanguinis), which 
serve to unite the receptaculum with the cavity of the hematodocha, are 
of such extreme fineness that they cannot serve as a conduit for the sperm 
into the hematodocha, and it is only the blood plasm which, under the 
pressure of the walls of the heematodocha, can be made to penetrate into 
the cavity of the receptaculum. Consequently, the role of the latter is 
