PACKARD.] THE JOINT-WORM. 693 



farmers to protect themselves is to dig trenches aronud their fields into which the crickets 

 fall iu enormous crowds and are killed by their own numbers. The upper individuals, 

 however, manage to make a bridge of the bodies of their companions, and sometimes 

 cross the ditches in great quantities. Pigs eat these insects very greedily. They seem 

 to be periodical in their appearance, the great swarms only occurring once in six years. 

 I think their depredations are mostly committed iu the night, as I saw none during tho 

 heat of the day, but toward twilight they swarmed on the stems of artemisia and other 

 low plants, and were exceedingly active." 



Description of Anabnis simplex. — Dai'k shining brown, posterior femora with an ex- 

 ternal and internal row of small spines beneath upon the posterior extremity; tibisa 

 angular, with a row of spines uy)on each side above, and two approximate rows beneath, 

 with the spines alternating. Length, fifteen lines, pronotum six, ovipositor twelve, pos- 

 terior femora and tibite, each eleven, and tarsi three and a half. This seems to be one 

 of the species which is eaten by the aborigines of tho Valley of the Great Salt Lake. — 

 (Haldeman in .Stansbury's Report, 1655, p. 372. 



Anabnis haldemani Girard. — Anteanaj long and filiform, reaching posteriorly the 

 base of the ovipositor; pronotum short, broad; femora smooth, yellowish ; feet and 

 ovipositor reddish-purple. Posterior margin of pronotum black, with two parallel 

 black bauds on the posterior third of its length. 



Description. — The abdomen above exhibits ten segments or articulations, the an- 

 terior or basal one being, as stated above, covered by the posterior prolongation of the 

 pronotum. Beneath there are seven subquadrangular plates, situated opposite to tho 

 seven middle upper segments. The posterior segments inclose another piece bearing 

 two spine-like abdominal appendages — one on each side. The ovipositor is as long as 

 the abdomen, and entirely smooth. The base of the antennae is situated above the 

 eyes, aiul inserted upon an angular movable piece. The joints composing these organs 

 are very short, and provided with minute setie. The tibiae are provided with four 

 rows of spines, two anterior and two posterior; the internal posterior row being the 

 stoutest. The posterior rows are more densely set with spines, while the latter are 

 scattered and alternate with each other in the anterior rows. The first and cordate 

 joint of the tarsi is the longest, the second is the shortest, and, from tho middle of the 

 third, a fourth slender and long joint arises, slightly convex above, and terminating 

 in two spines or claws curved inward and outward. The ground-color above and be- 

 low is yellowish ; the antenna?, limbs, and ovipositor are of a reddish-purple. The 

 posterior margin of the pronotum is black. Two parallel black vittae, inclosing a nar- 

 row yellow one, are observed on each side of the dorsal line, upon the posterior third 

 of the pronotum. The posterior portion of the upper abdominal segments is occasiou- 

 ajly of a deep-brown hue. 



This species difters from Anabrus simplex Hald., by a proportionally much shorter 

 pronotum. — (Girard in Marcy'a Keport of Explorations on the Red River of Texas, p. 



a48.) 



So large and conspiciions an insert as the Anabrus is easily kept 

 under by the means already suggested in treating of the locust. 



I^sSECTS SPECIALLY INJURIOUS TO ^Y^EAT, OATS, BAR- 

 LEY, ETC. 



A. — Affecting the root and stalk. 



The joint WORM, Isosoma liordei of Walsh, Eurytoma hordeiof Harris. 



A rainnte, footless, yellowish-white maggot forming blister-like swellings between 

 the second and third joints of the stalk, immediately above the lower joint in tho 

 sheathing-baso of the leaf; remaining through the winter in the stubble, straw, or 

 harvested grain, and changing into a small, slender, black, four-winged insect, which 

 deposits its eggs iu the stalks of young wheat late in May and in Juno. 



This insect, belonging to a group of chalcid flies which are, as a rule, 

 parasitic on other insects, is a vegetarian, and parasitic on the stalks of 

 wheat and other cereals, living on the sap, and by its presence causing 

 the formation of blister-like galls or tumors on the lower part of the 

 stalk. When the wheat or barley is from 8 to 10 inches high its growth 

 becomes suddenly checked, the lower leaves turn yellow, and the stalks 

 become bent. If the buts of the straw are now examined they will be 

 found to be irregularly swollen and discolored between the second and 

 third joints, and, instead of being hollow, are rendered solid, hard, 



