40 McIntosh, on the Greyariniform Parasite of Borlasia. 
faintly granular (not quite diaphanous), bluntly rounded, and 
marked by a slight swelling of the body at its base, from 
which swelling the snout gently tapers. There is no trace of 
rough points or other means for adhering. Sometimes, as 
when the investment had received injury, the surrounding 
water seemed to pass inwards and separate at certain parts 
the contained granules from the sheath, a fact which shows 
a certain degree of cohesion in the contents in situ . 
A favorable opportunity of examining the parasites was 
afforded by the spontaneous rupture of some of the annelids. 
They may then be seen projecting from the granular paren- 
chyma throughout their entire length, with the exception of 
the snout, by which they adhere. Indeed, this may often be 
seen in the perfect annelid, as the waves of the fluid in the 
general cavities bend hither and thither the free bodies of the 
gregarinax After remaining for some time in the previously 
mentioned position (under pressure), a few separate them- 
selves, and move through the salt water with a slow gliding 
motion like that of a diatome. On careful scrutiny the 
contour of the snout in a moving specimen is observed now 
and then to alter ; this motion is not due to currents between 
the glasses, and it moves through mucus in the same 
manner. After remaining eight or ten hours in water (salt) 
all motion ceases, and in some the body becomes altered, 
assuming a club-shaped appearance, as seen in fig. 3. At the 
same time the clear portion at the snout is almost obliterated 
by encroachment of the granules. 
Under pressure certain ova that accompany the gregarini- 
form bodies are often extruded from the posterior end of the 
two first-mentioned worms. In one example of the greenish 
variety ( Borlasia olivacea ) they w r ere emitted in August last 
in the form of an elongated cordon, held together by a slightly 
granular gelatinous matrix (fig. 6), the cord being rather 
more than the breadth of two ova, and the latter loosely 
scattered in the tissue. In the same specimen a mass of ova 
of a rounded form, enveloped in the same hyaline granular 
tissue, was subsequently discharged. These ova (fig. 5) 
measured about -r^th of an inch in diameter, and each con- 
tained an embryo that, for some time after the extrusion of 
the egg, made very evident movements. They have two 
coats, an inner, faintly (concentrically) striated under pres- 
sure, and an external, without markings. The contained 
embryo is finely granular, and has a large pale nucleus ; its 
various postures are seen in the outline (fig. 6). When an 
ovum is ruptured between the glasses the contents spread 
abroad as a vast number of dancing granules. 
