248 Benj. D. Wahh on the Inserts inhabiting the Galls 



coloration in another large group of genera, will always remain as a 

 curious example of what I have called Unity of Coloration. As in 

 other such cases, there exists here a definite Colorational Pattern, dis- 

 tinctly traceable through large groups of species, while in other large 

 groups this Pattern is more or less subobsolete, and in still other groups 

 the Pattern is entirely obsolete. 



The Teuthredinidous Willow-galls that are known to me may be 

 thus tabulated, so as to form the complement of the Synopsis of Ceci- 

 domyidous Willow-galls given in the former part of this Paper. fProc. 

 (Sec. III. pp. 575 — 6.) 



SYNOPSIS OF THE TEXTHREDIXIDOTJS GALLS OF THE GENUS SALIX 



(WILLOW.) 



A. Gall always monothalamous, and evident]}- a deformation of a bud. 



III. Bud simply enlarged; its leaves obliterated. I 16 » S 'S?, mma » n - S P- on S - 

 1 * ° J huinilis. 



B. Gall a deformation, and swelling of the bud itself. 



"I IT, S. ovum, n. sp. on S. 



4. Gall monothalamous, spongy, growing from J raata. 



the side of the twig. !' „ , 



° I 18, S. ovulum, n. sp. on S. 



J humilis. 



5. Gall a mere enlargement of the twig, poly- ") ln „ 



thalamous, pithy inside, with its cells all in- - t9 { 8 " n °? us ' n - ? P- ou s - 

 ternal. J longifolia. 



C. Gall growing out of the leaf, the shape and structure of the leaf still plainly 

 perceptible, monothalamous. 



f Quite large, and never, except very rarely, continent one with another. 



3. Spherical or short-oval, sessile. [ 20 > S " P omilni ; "• B P- on &• 



J cordata and S. discolor. 



4. Semicircular in outline, sessile. 1 21 > S " .fesmodioides.n. sp. 



J on to. humilis. 



5. Spherical', with a very short peduncle. ] 21 l is \ . S " P isum - n - s l>- on 



1 »i j g discolor. 



D. Xot represented. 



Genus EUTTRA. 

 This genus differs from Nematus in having only 3, not 4, submar- 

 ginal cells, the oue which is 3rd in Nematus being obsolete. Speci- 

 mens of Nematus are occasionally found with one of the two front, 

 wings like those of Euura ; e. g. 2 out of 10 N. s. desmodioides, n. sp., 

 1 out of 4 N. s. pisum, n. sp., and 4 out of 72 N. s. pomum, n. sp. In 

 a bred % of Nematus ventricosus Klug, (= Selandria ribis Winchell,) 

 both wings have only 3 submarginal cells, so that if captured at large 

 the specimen would naturally be referred to Euura. In Tenthredo, 

 Allantus } Selandria, &c, I notice many similar anomalies, proving 



