upon lepidopterous larrcs, &c. 289 



appropriately placed and highly conspicuous in the 

 terrifying attitude, must be at least as efficient in 

 causing alarm as a greater number of markings. And 

 as a matter of fact, in Prof. Weismann's figure of 

 C. porcdlus in the terrifying attitude, it is shown that 

 the single pair (which are by far the largest) on the 

 first abdominal segment are prominent and alone 

 produce any effect, the marks on the second abdominal 

 segment being insignificant and partially concealed, 

 while the marks repeated on other segments are of great 

 morphological interest, but of no functional importance. 

 Dr. Hickson informs me that the terrifying attitude was 

 very perfectly assumed by the larva, as we should 

 expect from the tapering of the body anteriorly and the 

 small head, by which the complete retraction into the 

 part possessing the eye-like marks is rendered possible. 

 All this is typical of CJuerocampa. It is noteworthy that 

 the anterior part of the marking extends on to the third 

 thoracic segment. The marking occurs as an inter- 

 ruption of the subdorsal line, thus indicating its origin 

 from the latter, as Prof. Weismann has shown, and the 

 line itself persists faintly along its whole length, existing 

 as a lightish and often interrupted stripe immediately 

 below the line in which the rather darker ground colour 

 of the dorsal area terminates. This arrangement 

 very much resembles that which I have previously de- 

 scribed in Smerinthus. The ground colour was green, as 

 in the young stages of Chcerocampa, and in a small pro- 

 portion of the mature larvae (in the two English species), 

 but it retains distinct traces of shagreening over the 

 whole surface, and the caudal horn is sprinkled with 

 typical hair-bearing tubercles. The persistence of the 

 shagreen dots upon the horn resembles Acherontia (and 

 other genera), but the general surface of the larva has 

 far more distinct traces of these structures than are 

 found in this genus. Very large white dots remain on the 

 sides of the third thoracic and first abdominal segments, 

 in the same situation which is marked by a conspicuous 

 light patch in Chcerocampa elpenor. The shape of the 

 caudal horn is peculiar, but very unlike that of 

 ( 'hcerocampa, being large and strongly curved down- 

 wards towards the apex, and tapering very suddenly 

 close to the point into a conical form. Except in the 

 last point, which, as far as I know, is peculiar, the 



