MORSE: ORTHOPTERA OF NEW ENGLAND. 371 
tion, produced by the very diminutive tegmina, is high-pitched 
and of but httle volume, but may be heard by keen ears at a 
distance of two or three rods. 
Although widely distributed these insects are scarce in New 
England, single examples or at most two or three at a time being 
met with now and then. Two species only are definitely known 
to inhabit New England, but a third should be sought for along 
our western border. 
Key to New England Species of Atlanticus. 
Hind femora two and one-half times as long as the pronotum. Male with 
tegmina but very little exposed; cerci acutely tipped and the inner tooth 
placed about half-way from tip to base. Female with subgenital plate 
split deeply, the lobes prolonged, sublanceolate. 
Long-legged Shield-backed Grasshopper, A. americanus, p. 371. 
Hind femora only twice as long as pronotum. Male with exposed part of 
tegmina three-fourths as long as pronotum; cerci blunt at tip, the inner 
tooth nearer the tip than base. Female with subgenital plate but moder- 
ately emarginate, the lobes arcuate, semicircular. 
Short-legged Shield-backed Grasshopper, A. testaceus, p. 372. 
Long-legged Shield-bearer. 
Atlanticus americanus (Saussure). 
Plate 14, fig. 15-17. 
Orchesticus americanus Saussure, Rev. et Mag. de Zool., ser. 2, vol. 11, p. 
201 (1859). 
Thyreonotus dorsalis Scudder, Boston Joum. Nat. Hist., vol. 7, p. 454 (1862). 
— Fernald, Orth. N. E., p. 26 (p. 110) (1888).— Smith, Rept. Ct. Bd. 
Agric. for 1872, p. 380 (1873).— Scudder, in Hitchcock's Geol. N. H., 
vol. 1, p. 320 (1874). 
Atlanticus dorsalis Walden, Bull. Geol. Nat. Hist. Surv. Ct., no. 16, p. 141 
(1911). 
Head but little prominent, smooth, the vertex narrowing 
anteriorly between the small round eyes to a blunt decurved ridge 
which is cut transversely on the face between the antennal pits 
by a narrow groove. Face broad and rounded. Pronotum 
prolonged backward over the first abdominal segment, slightly 
convex above both transversely and longitudinally, the disk 
broadening backward, convex behind, its sides gently sinuous, 
carinate at junction with lateral lobes, which are angulate with 
the disk. Presternum with a pair of prominent, slender spines. 
