322 PROCEEDINGS : BOSTON SOCIETY NATURAL HISTORY. 
ecdysis, shows as a transparent structureless membrane. The sections 
are nearly perfect as breaking of the separated cuticula does not tear 
the tissue. 
Salivary Glands. 
The tick has paired salivary structures. These lie on each side 
of the body nearer the anterior end and each is made up of two parts, 
the duct and the racemose gland. The salivary ducts resemble the 
tracheae in that they have a striated appearance due to thickenings 
of the walls. They differ in that the striation of the tracheae is finer 
and the tracheal branches are long, slender, and twisted, while the 
branching of the salivary duct is short and comparatively heavy. 
As has been said, the salivary ducts empty into the hinder part of 
the pharynx at the base of the mandibles and hypostome. For the 
duct on the right side see pi. 18, fig. 4, sal. dt. 
The glandular portion begins in front of the brain and extends to 
behind the stigmata. The duct and glandular portions together 
look much like a bunch of grapes (pi. 20, fig. 14). The description 
and figures given by Pagenstecher show conditions in Ixodes ricinus 
similar to these in Boophilus. In Ixodes, however, the glandular 
portion is not to be found in front of the brain nor behind the stig¬ 
mata. In the gravid female Boophilus the egg mass crowds the 
salivary system forward and to the sides and one preparation indi¬ 
cated a distinct degeneration of the salivary cells. Possibly this is 
to be correlated with the decrease in size of the anal portion of the 
intestine and the accumulation of renal concretions in the renal sac 
and Malpighian tubules. Each part of this racemose gland is sepa¬ 
rate from all other parts and has its own drainage duct which unites 
with another and these with others till the main duct is formed. 
The number of cells making up one of the glandular divisions is 
not constant, but there are certainly never more than ten nuclei to 
be seen and sometimes only one. 
Glands of the Skin. 
Boophilus has many glands which lie in the hypodermis and open 
to the exterior through large pores in the chitinous cuticula. There 
are also passageways for hairs which to a slight extent resemble the 
