598 [December 



clerical or typographical error, like the statement that the third joint 

 of the tarsi is '' the longest and most slender," whereas in all trne Ceci- 

 (Joini/tiia it is the second joint that is by far the longest of the five. The 

 dimensions, including those of the legs, agree exactly. Harris incor- 

 rectly gives the length as " a little over .20 inch," and the alar expanse 

 as '' rather more than .30 inch," {Inj. Ins. p. 567.) which makes the 

 expanse proportionally too little by nearly .08 inch, taking Dr. Fitch's 

 measiirements as the standard of comparison. 



No. 9. Gall S. triticoides. n. sp. — ^On S. eordata. A polythalamous, woody 

 gall .70 — 1.23 inch long and .30 — -.37 inch in diameter, bearing a remote resem- 

 blance to a head of wheat with the kernels elongated, naked, pointed and very 

 protuberant, its general outline oval or elongate-oval, and formed by the 

 swelling of a twig to 2 or 3 times its former diameter, the swelled portion being 

 very much contracted longitudinally, so as to bring each kernel-like bud nearlv 

 or quite into contact with the base of the one that precedes it in the same row. 

 the whole number being arranged in 4 irregular rows. Besides the swelling of 

 the twig itself, the origin of each bud is also swelled into a more or less large 

 tubercle, inside which is excavated longitudinally a cylindrical, slightly ru- 

 gose and moderately polished cell, .25 — .27 inch long and .06 inch wide, the bud 

 itself being elongated to about .17 inch and deformed so as to become a beak- 

 like, tubiliform continuation of the cell, without any suture on the inside inter- 

 vening, moderately polished inside like the woody part of the cell, and without 

 pubescence as at the interior tip of the cell of 8. cornu n. sp. Through a slit 

 at the tip of this beak-like bud the maker of the gall escapes, while, as usual, 

 the parasite that preys on the gall-maker bores through it laterally. Above 

 the gall the twig generally shrivels to about J its natural diameter, but occa- 

 sionally where there are only a few cells — say 7 or 8 instead of 15 or 16 — it is 

 not very materially diminished in size.— Described from 3 dead and dry speci- 

 mens. Very rare near Rock Island. 



Larva, pupa and iMA(iO are all unknown; but from the structure 

 of this gall being so exactly like that of *S'. siliqua n. sp. '( and espe- 

 cially aS. cornu n. sp., there can be no doubt that it is. like those two 

 galls, the work of a Cecidomijia . Inside several of the cells I found 

 cocoons similar to those of C. s. strohiloldes. &c.. but much longer in 

 proportion to their diameter, and not glued to the walls of the cell as in 

 S. siltqua and *S'. cornu, so that I was able after relaxing the gall to 

 extract two of them entire. They measured when extracted .42 — .44 

 inch in length and .06 inch in diameter, thus occupying the entire 

 length and breadth of the cell including the beak formed by the bud. 

 In the bottom of many of these cells, where the beak-like bud was bored 

 laterally, I found an empty cocoon very similar to that of a parasitic 



