On Sesia tipuliformis and Trochilium apiforme, Linn. 185 



Similar though much fainter touches inferiorly 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 tliat 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- 

 formis'f, t 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. Kirbj, F.L.S., F.E.S., &c. 

 [The accompanying paper was written in June 1888, and published 

 in ' Horee Societatis Eutomologicae 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 mio-bt be useful to 

 give the article a somewhat wider circulation. — W. F. K.j 



t [This insect is very rare in England, and fresh specimens would be 

 unattainable for dissection ; but tlie other two species discussed in this 

 paper are sufficiently abundant, — W. F. K.] 



