220 MAINE AGRICULTURAL EXPERIMENT STATION. I91O. 



1880. Tetraneura ulnii, Lichtenstein, Les Pucerons des Ormeaux. La 



Feuille des Jeunes Naturalistes. Aout Sept. pp. 1-7. 



1881. Tetraneura ulmi, Buckton. British Aphides. Vol. Ill, pp. 131- 



135, Plate CXIV, figs. 5-13. 

 1895. Tetraneura ulmi, Judeich und Nitsche. Porst-insektenkunde 



Band II, p. 1208 and Fig. 329 c. 

 1896-1897. Tetraneura ulmi DeGeer, Cholodkovsky. Zool. Anz., 1896 

 No. 520, pp. 508-513; (rev. in Zool. Centbl, 4 (1897), 

 No. 26, pp. 918-919. By O. NiissHn (Karlsruhe). 

 (1899) Tetraneura ulmi, Cholodkovsky. Zool. Ans., 22 No. 602, pp. 



468-477. Descriptive and biological ,notes on several species 



of plant-lice. 

 1902. Tetraneura ulmi, Kerner. Nat. Hist, of Plants. Vol. II, p. 533. 



Figure of galls. 

 1902. Tetraneura ulmi, Connold. British Vegetable Galls, pp. 247-248. 



Plate 108. Description and photograph of galls. 



PEMPHIGUS ULMIFUSUS 



(The Red-Elm Gall-louse produces an erect spindle-shaped 

 gall about i inch in height on the upper side of the leaf of the 

 red or slippery elm, — UIiiius pnhcsccns Walt., fiilva Michx. 

 Fig. 150). 



This insect which was named in 1869 with only a few words 

 of descriptive comment, remained with no real description until 

 1904, when it received that attention under the name of Schiso- 

 ncura sp. by reason of a specimen with a branched M as is not 

 infrequent for this species. The appended bibliography gives 

 a brief outline of the character of the discussions, for the most 

 part meagre, which have been given this species during the 40 

 years since it was recorded by Walsh. So far as has been au- 

 thentically determined the gall is known to occur only on the 

 red or slippery elm, — Ulinns piihcscens Walt., fnlva Michx., 

 and the accounts which record it from U-lmiis amcricana are 

 probably in error. 



My own acquaintance with this species is limited to Minne- 

 sota material given me by Professor Oestlund and Illinois ma- 

 terial loaned me by Mr. Davis from the Thomas collection and 

 his own recent collections. From these, I was able to make 

 the following measurements and present figures 146-150. 



Total body length 2.15 mm. to tips of closed wings, which is 

 approximately the same as Walsh's 0.07 inch for the same 

 measurement. Wing expanse 3.8 mm.-4.5 mm. Antenna 

 6-jointed; III, 0.22 mm.-0.26 mm.; IV, 0.09 mm.-o.i mm.; V, 



