ANATOMY OF THE LARVA OF ALETIA. 
47 
the two lips, and so close the opening between them ; the other part is 
attached to the neighboring epidermis, and serves to open the lips. 
Only this latter division of the muscle, which is considerably the larger, 
was described by Landois.* 
The internal anatomy of the larva agrees closely with the lepidopte- 
rous type, as established by previous observers. In the head, Plate VII, 
Fig. 1, the digestive canal begins with the large mouth Nt, lined by a 
dark, firm cuticula and passing over into the narrow muscular oesopha- 
gus, Oc. Behind the mouth is a projecting pointed process at the tip 
of which opens the salivary duct. Above and in front of the mouth 
there is a distinct mass of Tissue, of a fibrous, areolar character, spread- 
ing out fan-like from the upper wall of the oesophagus and attached 
in front to the lower part of the clypeus and to an endocranial pro- 
cess. In this ma88 bf tisane lies the small frontal ganglion. Above the 
oesophagus is the brain, br; below it the subcesophageal ganglion S y 
connected by a short commissure with the first ganglion of the ventral 
chain. 
The rest of the internal anatomy is illustrated by Fig. 1, Plate VI. In 
the first (thoracic) segment the (esophagus expands into the enormous 
Btomaob A., which runs through eight segments, and is by far the larg- 
est ami moot eonspi nous organ of (he body. From in front backwards 
it gradually widens, but posteriorly it is rounded <uT. Into the hinder 
end open the malpighian or urinary T C OBOl a M, c, six in number, three 
on each side uniting together and opening by a short duct. The sali- 
vary glands lie upon each side of the stomach, having long ducts 
which reach through the anterior three segments of the body. The 
gland proper, Sal, is an elongate d tube, gradually diminishing in diam- 
eter towards its posterior end or tip; its course is curious; it runs some 
distance straight backwards, then makes a sharp angle over the second 
proleg and runs forwards and upwards, then another sharp crook over 
the first proleg and it continues backwards again an . slightly upwards. 
Behind the stomach the intestinal canal consists of four parts: first a 
short, constricted connecting piece; second a dilated, oval division, In.; 
third the short rectum li.; fourth the short anal tube. The dorsal ves- 
sel or heart, d. i\, is a long tube placed above the digestive canal, and 
extending through nearly the entire length of the body. The ventral 
chain of ganglia numbers eleven distinct knots, the last being however 
evidently double. The first veutral ganglion is the subcesop.iageal ; 
the second lies so near it as to be almost united with it. The others lie 
at regular intervals, until the tenth, which is pushed a little forward of 
its original position over the fourth proleg. The eleventh double gan- 
glion lies close to the tenth and gives off a large number of nerves, 
most of which run backwards. 
The large stomach alone represents the entodermic canal, and presents 
* Landoia. Zeit. wiss. Zoologie, 1867. 
