Vorhies—Larva of Phityphylax Designatus. Ill 
divides, the four subdivisions supplying the head only. The 
dorsal branch (A) will be described first. One of its two 
branches lies ventral to the other for a short distance, then 
curves outward and passes through the muscles directly to the 
eye, giving off several small branches which at once break up 
in the muscles. From a point near the eye this branch then 
curves inward again and, after making a dip posteriorly, where 
it gives off a small branch, it curves caudad and ventrad and 
passes beneath the brain, giving off a small branch to that organ, 
and then another small branch which anastomoses below the 
brain and dorsal to the oesophagus with its fellow of the op¬ 
posite side. From here this trachea may be considered as a 
branch of the ventral trachea (B) with which it is continuous. 
The dorsal branch of A passes slightly inward so as to lie along¬ 
side the corresponding opposite tracheae, giving off immediately 
after entering the head a branch on the outer side which curves 
upward and breaks up in the muscles of the top of the head. 
At a point posterior to the brain the main trachea forks, the 
inner, larger branch, immediately anastomosing with its oppose 
ite, while the outer, smaller one, curves outward and upward 
and breaks up in the muscles. From the point of anastomosis 
a median trachea passes forward dorsal to the brain and sup¬ 
plies the muscles of the labrum. 
Trachea B divides into two nearly equal branches before en¬ 
tering the head. The outer one curves outward and passes in a 
direction nearly identical with the outer branch of A but at a 
lower level, giving off small branches to the muscles, and finally 
ending in the mandible. The muscles supplied by this branch 
seem to be mostly mandibular. The inner branch of B passes 
cephalad and only slightly inward, the first important branch 
being found posterior to the median anastomosis of A. This 
branch soon divides, a small part passing forward to the mouth 
and the main part passing upward to anastomose with the 
branch described from A. Another important branch from the 
inner fork of B passes outward and forward and supplies mus¬ 
cles which seem to be manibular. The remaining portion again 
divides into two parts which pass forward and break up in the 
muscles of the floor of the mouth. Between the first and second 
