248 the entomologist's record. 



to a place in the list of occasional visitors to our country. I know 

 nothing of the lifehistory of this insect (T. fimbrialis), except what I can 

 gather from this note. It appears to he not a tree-feeding species, and 

 to frequent non-wooded places, while thyme is, at least, one of its 

 foodplants. I have had the pleasure of examining Mr. Prout's series 

 and wondered, I must confess, why the authorities had seen fit to 

 separate it, generically, as well as specifically, from Hemithea aestivaria. 

 It appears, however, that the distinction is structural, if not very 

 obvious. The structure of the antennae, and of the legs, with, above 

 all, a striking concavity above the tail on the hindwing, are the marks 

 of the genus Thalera. Otherwise T. fimbrialis is wonderfully like 

 H. aestivaria in colour, and general appearance, except that the fringes 

 on all the wings are dotted with red-brown, instead of dark grey. The 

 concavity in the margin of the hindwing does not appear to be very 

 constant in extent. One would like to complete the comparison with 

 freshly-emerged or -caught specimens, for both species appear to fade 

 in the same manner, and to the same extent. I would endorse 

 the hope expressed above, that those who collect in likely places, will 

 keep a sharp lookout for this insect. 



The young larva of Hemithea aestivaria, is a much more difficult 

 one to deal with, than those which I have taken in hand before, and 

 I have, in my accustomed diagrams, finished the task, with the con- 

 viction that its complications, and obscurities, would occupy a truly 

 scientific person for well nigh a life-time. Small, very transparent, 

 with almost undiscoverable organs, in its earliest stages — the only 

 comfort I have is that others, with better eyes than mine, are quite 

 as unable to make out the details as myself. 



This larva is not a clothing larva, any more than is that of 

 Geometra papilionaria, hut it shows just as that does a very close 

 approach to the habit. Mr. Bacot observes in a note which he made 

 on these larvae : " The silken threads which they spin about their 

 bodies, cling to, and afford a hold to foreign matters such as dust 

 and dirt," and I have found that one of my chief difficulties in tracing 

 the more obscure or transparent organs, has been the accumulation 

 of these foreign matters upon, or about them, and concealing the 

 details. 



In my paper on Geometra papilionaria, I mentioned, in passing, the 

 close resemblance, which, on a cursory examinination, this larva in its 

 earliest stage, bears to that which is now under consideration, and I 

 paralleled this resemblance with the position of Butler's prasina in 

 the general collection at the British Museum, an insect closely 

 resembling (again the examination was but cursory) H. aestivaria, 

 except for its much greater size. 



As a matter of fact, further, and more careful examination 

 somewhat modified my conclusions with respect to the larva, and, 

 before my paper was published in the Kntom. Record (vol. xvii., pp. 200 

 et seq.), I was able to add a note to the effect, that the larval 

 resemblance is as great to Comibaena pustulata, as to Geometra 

 papilionaria. Such is the case, as all may perceive by comparing 

 my drawings. It is also quite possible that I mistook the position 

 of the giant prasina in the Museum drawers as intentional, whereas 

 its place may have been 1 rought about more by the question of spare 

 room, than by an acknowledged relationship to Geometra papilionaria, 



