THE AMERICAN ENTOMOLOGIST. 



25 



one commonly found in the moi-e northerly parts 

 of the Northern States, where it usually takes 

 the place of the Striped Blister-beetle figured 

 above. It is of a uniform ash-gray color ; but 

 tliis color is given it by the presence upon its 

 body of minute ash-gray scales or short hairs, 

 and whenever these are rubbed oil', wliich hap- 

 pens almost as readily as on the wings of a but- 

 terfly, the original black color of its hide appears. 

 It attacks not only potato vines, but also honey- 

 locusts, and especially the English or "Windsor 

 beau. In one particular year, we have known 

 them, in conjunction with about equal numbers 

 of the common Kose-bug (Macrodactylus sub- 

 spinosus, Linu.), to swarm upon every apple 

 tree in a small orchard in Northern Illinois, not 

 only eating the foliage, but gnawing into the 

 young apples. In 1868 they have been quite 

 common in parts of Illiuois, Missouri, Wiscon- 

 sin, and Iowa ; and the people there had got so 

 habituated to the presence of the Colorado bug, 

 that in many cases they thought the Ash-gray 

 gentleman was a fresh invader from the region 

 of the Rocky Mountains ; whereas it has existed 

 everywhere in the more northerly parts of the 

 United States for time immemorial. 



The Black-rat Blister-beetle (Lytta 

 murina,* LeCoute). — Of this species (Fig. 

 14 b), which is entirely black, we received num- 

 erous living specimens in July, 1867, from D. 

 W. KaulDnan, Esq., Pres. Iowa State Hort. 

 Society, with an account of its swarming in that 

 month upon* the potato vines near Des Moines, 

 Iowa. There is a very similar species, the 

 Black Blister-beetle (Lytta atrata, Fabr.), from 

 which the Black-rat Blister-beetle is distinguish- 

 able only by having four raised lines placed 

 lengthways upon each wing-case, and by the 



dilated; wliiuli is also the case with the species next to be 

 referred to. (Fig. 14 d, represents the male antenna;, above; 

 that of I'cniale below.) Hence, in splitting up the extensive 

 and unwieldy old genus {Lytta) , these and certain allied 

 species have been very properly placed in a genus by them- 

 selves (Macrobatis) ; while the Striped Blister-beetle and the 

 Margined Blister-beetle, not possessing this i^eculiarity, are 

 grouped together under a distinct genus (Epicauta) . Practi- 

 cal men, however, who do not desii'e to trouljle their heads 

 with these niceties, will find it most convenient to class 

 them all together under the old genus {Lytta) ; and this we 

 have accordingly done. 



•The Latin word "murina" properly means "mouse- 

 colored;" and it is not easy to imderstand, why a,' black 

 insect should receive the specific name of ' ' mouse-colored. ' ' 

 We have got over tlie difUcidty by supposing that the author 

 of the name referred to the color of the black rat — the mm 

 rallui of Linnieus— formerly the only rat that ti'oubled us in 

 America, but now abuost completely driven out by another 

 imported species — the Brown or Norway rat — just as the im- 

 ported white man is at the present day gradually extirpating 

 the Red Indian, and the Bed Indian formerly drove south- 

 wards his mound-building Aztec predecessors. 



two first joints of the antennae being greatly 

 dilated and lengthened in the males, as above 

 in Fig. 14 c. This latter species has been cur- 

 rently asserted by authors to infest the potato 

 vine. "We believe that in many cases, at all 

 events, tliis is an en-or; and that the latter 

 species has been mistaken for the former. The 

 true Black Blister-beetle we have never met 

 with, except quite late in the year, namely 

 about the last of August or the fore part of 

 September ; and then always upou the flowers 

 of the Golden-rod, the Tliistle, etc. The experi- 

 ence of Ml-. Ulke, of "Waslungton, D. C, to 

 whom we referred upou this subject, coincides 

 with ours ; and surely a beetle wliich does not 

 make its appearance till so late a period in the 

 year as the last of August can scarcely ever be 

 injurious to the potato-crop. It would be very 

 desirable that persons meeting with Blister-bee- 

 tles, of a black color and without any pale 

 markings whatever, upon potato vines, at any 

 period of the j^ear, should forward specimens to 

 us. The question to be decided is certainly of 

 no very great practical importance ; but scien- 

 tifically considered, it is a curious and interest- 

 ing one, as tending to demonstrate that even the 

 very best entomologists are not universally 

 infallible. 

 The Margined Blister-beetle* (Lytta mar- 

 [Fig. 15.] ginata, Fabr.) — Tliis species (Fig. 15) 

 may be at once recognized by its 

 general black color, and the narrow 

 ash-gray edging to its wing-cases. It 

 usually feeds on certain wild plants ; 

 , __, , but Mr. Barber, of "Wisconsin, found 

 //^■\\ it, but only in small numbers, on Ms 

 I •mf^ I p^^^^^ vines in 1866 ; and in 1868 we 

 / \ were shown three specimens taken 



Sd°a^?^oy. on potato vines near Champaign, 

 Central Illinois, in company with the Striped 

 Blister-beetle. In the same year, 1868, it was 

 more abundant than any other species in a potato 

 field in Union county. Southern IlUnois. 



•This is the name formerly given by almost all entomolo- 

 gists to this species; and a most appropriate one it is, in 

 view of the remarkable ash-gray margin of its black wing- 

 cases (elytra) . But of late years it has been discovered, 

 that, as long ago as the middle of the last centuiy, and 

 several years before Fabricius named and described this 

 insect as the "Margined Blister-beetle" {Lytta marginata), 

 it was named and described as the ' ' Ash-gi-ay Blister-bee- 

 tle" {Lytta cinerea), by Foerster. Hence, in accordance 

 with the inexorable "law of priority,'" the obedient scien- 

 tific world has been called upon to adopt Foerster's name for 

 this species; and as two species belonging to the same genus 

 can not, of course, have the same specific name, the true 

 Ash-gray Blister-beetle of Fabricius {Lytta cinerea) , which 

 is really ash-gray aU over, has been re-christened by the 

 name of " Fabricius's Blister-beetle" {Lytta Fabridi) . 

 Positively, this continual chopping and changing in scientific 



