IIEPORT OF THE SOCIETY . 39 



THE LARCH APHIS 



By Dr. J. C. Chapais, St. Denis, Kamouraska 



About the middle of June, 1920, while I was making my Spring inspection 

 of the trees of my arl)oretum, which contains a few fine specimens of the Amer- 

 ican Larch (Larix Americana) (vulgo : Epinette Rouge, Tamarack), I thought 

 that the new Spring growth of one of them had a strange appearance and, on 

 looking at it more attentively, I found that part of the tips of the new twigs 

 w^ere loaded with a mixture of sticky honej-dew, of numerous specimens of large 

 dark aphides provided with very long legs, and of quite a host of very lively 

 tiny black ants. In this mixture the new Spring needles or leaves of the twigs 

 looked rather sickly. I was, evidently, in the presence of a new insect, 

 uterly unknown to me. 



As I usually do in such circumstances, I decided to send a few specimens 

 of the twigs bearing this mixture to Mr. W. Lochhead, Professor of Biology 

 at Macdonald College, to get from him some information concerning this new 

 and verj' strange looking visitor to mj' larches. As usual, Mr. Lochhead very 

 willingly sent me his answer, which was that I had to deal with a larch aphis 

 very probably Lachniis laricijex. Fitch, and that I would get more inform- 

 ation on this subject if I could get hold of a bulletin of the Orono, Alaine, Agric- 

 ultural Experiment Station, entitled : ''Bulletin 202 — July — Aphid Pests of 

 Maine : Food Plants of the Aphides ; Psyllid Notes." Following ]\Ir. Loch- 

 head's advice, I got the above mentioned Bulletin, written by Dr. Edith ]M. 

 Patch, from which I have extracted the following information concerning what 

 is, very probably, Lachnns laricijex. 



In this Bulletin, jNIiss Patch, one of the best LTnited States authorities on 

 the Aphididse family, gives some notes on various species of Aphides, one species 

 found on ferns, ten species on conifers, besides six species of the genus Lachnus, 

 a sub-family of Aphididse amongst which was mentioned one which seems, very 

 likel}^ to be the species found on one of my own larches. Miss Patch has this 

 to say about it : 



"Lachnus laricijex, Fitch. What is apparently this species of Fitch is 

 not uncommon on the larch (L. laticina, Koch) in Maine. Packard (1890) 

 quotes the original description, and records scattered individuals from Augusta, 

 Maine. No figures have been published for this larch aphis in America. 



Cholodkovsky (1899), however, figures a larch species, maculosm Cholod- 

 kovsk}', which is certainly closely allied to the Maine material and may perhaps 

 be the same. 



