AN ICHTHY0BDELL1D PARASITIC ON SAND WHITING. 23 
In 1913 Sukatschoff described similar glands in Brancliel- 
lion, and compares them to the oesophageal glands of 
Haementeria costata described by Ko wale vsky (1900), and 
to similar glands of Clepsine plana figured by Whitman 
(1891); Hemmingway (1912) found them also in the Grlos- 
siphonid leeches Placobdella pediculata and P. para- 
sitica. 
Both Johansson and Sukatschoff state that they are 
glandular organs and that fish blood-corpuscles are not found 
in them, and I agree with them. 
The nuclei of the epithelial cells which line these glands are 
of the same character as those of the following pouches of the 
thin-walled parts of the middle gut, but they are larger, some 
being twice the size. 
At the level of the opening of the female pore that is just 
below the 12th nerve ganglion the second pair of pockets of 
the anterior entodermal gut is given off (Text-fig. 6, A. g.). 
They have wide openings into the gut and are somewhat con- 
voluted at their blind ends. These pouches appear to corre- 
spond to those figured in Branch ellion by Sukatschoff 
(fig. 85, V. d. t. 2), and are homologous with the following 
six pairs of the anterior thin-walled division of the middle 
gut. Their difference in form is caused by their being pressed 
forward by the cocoon gland ducts, which prevent lateral 
distention. Behind this pair of pouches there is a sphincter 
of annular muscle fibres. 
Following the anterior entodermal gut is the middle gut, 
which is divdded into — 
(1) An anterior thin-walled part (Text-fig. 6, A.m.g.). 
(2) The blind gut (Text-fig. 6, B.g.). 
(3) A dorsal thick-walled part (Text-fig. 6, M. g.). 
The anterior thin-walled division of the middle gut lies in 
the testicular region, and consists of a small median tube 
from which are given off six pairs of caeca opposite to nerve 
ganglia 14 to 19 inclusive. The position and form of these 
six pairs of caeca are shown in Text-fig. 6, A. m. g. 
These pouches are lobed at their blind ends by the presence- 
