310 PROCEEDINGS OF THE 



while in the species under consideration they are decidedly longer 

 than that; nor can I think that Hartig's terms, " so lang wie der 

 Hinterleib," can apply. But there are other differences ; thus 

 Thomson (loc. cit.) calls the terebra, " longa," and " terebra val- 

 vulis feniorum longitudine, apice postabdomen longius superante;" 

 and he says also of the male, " antennis subtus brunneis;" and 

 " ventre nigro," words which show conclusively that the Strath- 

 blane saw-fly must be distinct ; and I have not been able to 

 identify it with any of the other described Nemati. 



Snellen van Yollenhoven has described a small species which he 

 bred from the spruce, under the name of N. solea; * but it has 

 no likeness with furvescens, which can scarcely be even the laricis 

 of Hartig; for, according to that author's description, laricis has 

 the antennse " dick, kaum borstenformig;" whilst the exact oppo- 

 site is the case with my insect; and Hartig also says, " Der 

 behaarte Thorax mit kleinem blassem Fleck in der Hinterecken, 

 der Halskragens, Riickenkornchen rein weifs; Hinterleib einfarbig 

 scliAvarz;" while in furvescens the whole of the pronotum is white, 

 the cenchri are scarcely (if at all) visible, the anal segment and 

 ventral more or less pale ; and it is only with a strong lens, and 

 sideways, that I can see any hairs on the thorax. 



With regard to the affinities of this species, I thought first that 

 it was allied to the Ahietum group; but the alar cell structure and 

 colour would seem to show that it is related to N. fulvipes, Fall.; 

 and appendiculatus, Htg. (or rather with N. ruficornis, Oliver; for 

 that seems to me to be the proper name for appendiculatus, Hartig; 

 of wdiich fraxini and crassicornis of the same author, are only 

 varieties, as I know, from having bred them. I can see no dif- 

 ference between the birch and willow-feeding larva of fraxini, 

 and the currant-feeding larva of appendiculatus, as figured and 

 described by van Vollenhoven ; while with the imagos, I can 

 find no satisfactory marks of distinction, beyond colour : and it 

 is easily seen that the various so-called species are mainly differ- 

 entiated by the greater or lesser amount of black and white with, 

 which they are adorned; and even in structure and form I think 

 that they vary inter se. Probably, also, one or two of Thomson's 

 species may be referred to ruficornis). 



* Van Vollenhoven himself suspects that solea, of which he only knows the 

 male, may be merely the undescribed male of laricis. 



