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Prof. E. K. Brandt on the Anatomy of 
cavities or air-vessels are not yet tracheae. In this respect 
the Sesiidae differ much from the Sphingidse, in which they 
are placed together in one cluster in front, and in which such 
vesicles or sacs are absent in the transverse branches of the 
tracheae on the ventral surface. 
The male sexual apparatus of S. tipuliformis consists of the 
following parts : — (1) the testes, (2) the deferent ducts, (3) 
the vesiculce seminales , (4) the ductus ejaculatorius , (5) the 
penis, (6) the accessory glands. 
The testes , as is invariably the case in Lepidoptera, are two 
in number, and are enclosed in a common sac or scrotum. 
The deferent ducts are short and broad, opening into the 
vesiculce seminales , which are small oblong sacs. The ductus 
ejaculatorius is a long sinuous tube. The penis is horny, 
with a guitar-shaped depression in the middle. The accessory 
glands are long and very sinuous. 
The female sexual apparatus of S. tipuliformis consists of 
the following parts : — (1) the two ovaries, (2) the oviduct, 
(3) the vagina, (4) two accessory glands, (5) receptaculum 
seminis , (6) unpaired accessory gland, (7) copulatory pouch, 
and (8) ovipositor. 
While investigating the anatomy of Sesia scoliceformis I 
noted a remarkable peculiarity in the structure of the ovaries. 
Each ovary contains fourteen tubes, each of which emits a 
small excretory canal. Every two canals unite, forming 
seven egg-tubes, which then combine to form one oviduct on 
each side, and afterwards unite at the vagina. This pecu- 
liarity in the structure of the ovaries is very remarkable and 
constitutes an exception to their usual type in Lepidoptera. 
In all other Lepidoptera hitherto examined there are only 
four egg-tubes in each ovary. It would be very interesting 
to discover whether the same anomaly in the structure of the 
ovaries is to be met with in other species of Sesia , or whether 
it is peculiar to S. scoliceformis. On dissecting S. tipuli- 
formis I found that it exhibited the normal structure of the 
ovaries. I only count four egg-tubes in each ovary. These 
ducts are long, rather narrow, and only slightly constricted, 
so that they form straight rather than undulating tubes. 
The short broad oviducts open into the long vagina, which is 
considerably dilated at the end. There are two accessory 
glands, each of which is constructed of a broad pear-shaped 
part, opening into the vagina, and a long narrow tube, coiled 
in the peritoneal cavity. The unpaired supplementary gland 
consists of a long, narrow, stalk-like tube, opening at the 
lower end of the vagina. The receptaculum seminis is a long 
narrow tube, with the rounded end coiled in the cavity of the 
