1804.] 595 



figured as sessile and those of his $ antennae as pedicelled — described 

 the S as 9 and the $ as S . and mistaken the % anal forceps for an ovi- 

 duct ; and since the S [ ? ] antennfe are said to be 2(l-jointed. his statement 

 that the 9 [S ] antennae are 16-jointed must surely be either a clerical 

 or typographical error, for in Cecutomi/ia the S always has at least as 

 many antenna! joints as the 9 . {Dipt. N. A. p. 175.) It is possible. 

 on the assumption that there is no clerical or typographical error here, 

 that he might have bred from these galls the % of some inquilinous 

 species unknown to me, which, like my inquilinous Cec. albovittata. 

 had a much smaller number of antennal joints than the author of the 

 gall which it inhabited, and so mistaken it for the other sex of the 9 

 that really makes the gall. As will be shown below, the gall-making 

 C. s. batatas, which has % antennae 18 — 19 jointed, sometimes on S. 

 humilis oviposits on the same twig as C. s. siliqua. so that the two galls 

 run together. But no one could mistake the % of that species for the 

 S of C. s. siliqua, from its very diiferent size and coloration. After 

 making the necessary allowances, however, I do not see that this imago 

 can be satisfactorily separated from my species. Below will be found. 

 in a condensed form, the leading points in Dr. Fitch's descriptions, 

 omitting such details as are of a generic, rather than of a specific cha- 

 racter. 



"Gall Salicis Fitch {^^^rigidoe 0. S.) Plate II. fig. 7.— Formed at the tips of the 

 twigs of several willows growing to the size of shrubs or small trees, of an oval 

 or long ovate form, from 3 to li inch long, i inch in diameter at the broadest 

 part, externally red, yellow or greenish brown, being the same color as that of 

 tlie particular twig upon which it grows. Some of the natural buds of the shrub 

 often occur upon the surface of the gall, as bright and vigorous as they are on 

 the unaffected branches. Frequently one or two twigs grow from its sides, aj)- 

 pearing so well nourished and thrifty through the winter season, that we could 

 scarcely deem they were destined to perish the ensuing summer, did not an in- 

 spection of the old galls show their similar shoots almost invariably rotten and 

 decaying. Three-eighths of the upper end of the gall is dry, brown and brittle, 

 curving to a point like the kernel of Ergot or spurred rye and protruding from 

 the gall, a well-marked line of separation occurring at the junction of the dead 

 with the lower, living portion. Within, its substance is of a greenish white 

 color and of a soft woody texture. A cylindrical canal, .10 inch in diameter, 

 within which the larva lies, runs from the base of tne gall to the apex of the 

 brittle horn at the summit. The extreme tip of the horn is so brittle that it is 

 easily broken by the slightest touch and is rarely found entire. 



'• Larva. Plate II. fig. 3. — A small worm of a bright orange color, with the ante- 



