I 



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fiiscniiS or Mack stripes extending, one over the top of the head and pro- 

 notum and the other two on the lateral lobes of the pronotum and upon 

 the sides of the head. Laiipenms differs in coloration distinctly from the 

 two last mentioned species but only slightly from niveus. Like the latter 

 its general color is ivory white with the elytra perfectly transparent, but 

 it is distinct from niveus and the other two species in having the head and 

 the basal half of the antennas suffused with pink or light brown. It also 

 lacks very generally if not always, the fuscous spots which are always 

 found upon the lower face of the two basal joints of the antennae. Niveus 

 is farther distinguished from all other species by its proportionally longer 

 maxillarv palpi. This disproportion is rnost apparent in the ultnnate joint 

 which is not only relatively but actually longer than the same joint in 

 latipennis, a decidedly larger insect. These dimensions are for the two 

 species mentioned respectively: fifth joint 1.5 mm. and 1.4 mm; fourth 

 joint 1.3 mm. and 1.3 mm.; third joint 1.6 mm. and 1.7 mm. Finally 

 in niveus the outer, or fourth, curved oblique nerve at the base of the 

 elytra is more angular than in any of the other species and consequently 

 the space between the third and fourth nerves, which in the other species 

 is about equal in width to the space between the first and second and the 

 second and third, is in niveus much greater. In addition to the distinct- 

 ions already mentioned, y^z5art/?« has longer antennselhan the other spe- 

 cies have, these organs being more than tw'o and one-half times the length 

 of the insect. It is also remarkable for having the longer series of spines 

 at the tip of the posterior tibiae very large, for this genus, strong and acute. 

 The ovipositor of the female is also distinct from the perfectly straight 

 ovipositor of «?t'^?/5 in being plainly turned up at the tip. Finally the 

 maxillary palpi (.ifter distinct specific characters in the proportionally short 

 fourth joint and in the shape of the fifth joint which is subclavate instead 

 of fusiform as in the other species. Angustipennis differs from the other 

 forms in its small head and slender pronotum, which in the female, especi- 

 all}', is decidedly narrowed anteriorly, instead of being equal in w^idth 

 throughout as in the females o{ niveus and iatipennis. The hind legs are 

 also proportionally longer and more slender, and the post tibial apical 

 spines are so weak as to be somewhat difficult to distinguish with the 

 unaided eye. These species differ from one another in song as markedly 

 as in structure. That o{ niveus is the well-known irrr-ree, trrr-ree, re- 

 peated without variation or pause sixty or seventy times in a minute. In 

 the vicinity of Davenport this song is heard as early as the twenty-third 

 of July and it continues until the persistent little singers are killed by the 

 heavy frosts of late Fall. This song is heard only at night and occasion- 

 ally on cloudy days but in the latter case it is only an isolated song and 

 never the full chorus of the night-song whose vibrations in exact unison 

 produce that "rhythmic beat" as Burroughs has happily phrased it, 

 which is so characteristic. It is the effect of many united songs that has 

 led the same author to speak of "purring crickets." Thoreau calls it 

 the "slumbrous breathing" and the " intenser dream" of crickets, but 

 Hawthorne has given it a still more spiritual interpretation. He describes 

 it as " audible stillness," and declares that "if moonlight could be heard 

 it would sound like that." Prof C V. Riley says of the song of Iati- 

 pennis that it is continuous and recalls the trilling of a high-pitched dog- 

 whistle in the distance." He also says "The commingled shrill of this 



