On Sesia tipuliformis and Trochilium apiforme, Linn . 185 
Similar though much fainter touches interiorly proceed on 
the anal fin. Traces of the line of pigment seen at the 
younger stage a little above the ventral border of the abdo- 
men are still present; but all the reticulations just described 
have been developed subsequently and independently. The 
median ventral pigment-line is also quite distinct from the 
branch iostegal region to the vent. The modification of the 
numerous and somewhat small lateral reticulations into the 
larger vertical bars of the adult is easily observed in a series, 
as also the gradual diminution of the pectorals. A charac- 
teristic feature of this young stage is the presence of a K- 
shaped arrangement of black pigment on each side of the 
head, the strong bar of the K uniting with its fellow over 
the brain and proceeding forward over the eye to the tip of 
the snout. One leg of the K goes from the eye straight 
downward to the edge of the mandible, while the other 
slopes backward to the opercular region. 
The earlier stage here described would appear to represent 
a season’s growth, and, indeed, it is possible that the later 
stage referred to is a form about two months older. 
XXIII. — On the Anatomy of Sesia tipuliformis and Tro- 
chilium apiforme, Linn . By Prof. E. K. Brandt^. 
Two years ago, while studying the anatomy of Sesia scolice - 
for mis f I discovered that the structure of the moth differs much 
from the usual Lepidopterous type, and I thought it would be 
interesting to compare the connexion between the outward 
form and the internal structure of other moths belonging to 
the same group. In the summer of 1887 I had an oppor- 
tunity of dissecting several specimens of Sesia tipuliformis 
and Trochilium apiforme , and ascertained by repeated experi- 
ments that they agreed in most essential points. 
* Translated from the Russian by W. F. Kirby, F.L.S., F.E.S., &c. 
[The accompanying paper was written in June 1888, and published 
in ‘ Horae Societatis Entomologicae Rossicae/ vol. xxxii. pp. 41-49, in 
1889. I have not seen any translation or abstract elsewhere ; and as the 
subject, relating to a very aberrant group of Lepidoptera, is of consider- 
able interest and importance, and the languages of Eastern Europe are at 
present unfamiliar to many entomologists, I thought it might be useful to 
give the article a somewhat wider circulation. — W. F. K.] 
t [This insect is very rare in England, and fresh specimens would be 
unattainable for dissection ; but the other two species discussed in this 
paper are sufficiently abundant. — W. F. K.] 
