526 CLASS VIII. 
Campylus Fiscu., Exophthalmus Latr. Head behind the eyes 
exsert from thorax. Eyes large, globose. Body elongate, almost 
linear. 
Sp. Campylus linearis, Elater linearis L. (and Elater mesomelus ejusd.), 
Panzer Deutschl. Ins. Heft 8, Tab. 11. 
Elater nob. Head received in thorax as far as the posterior 
margin of the eyes. 
Sub-genera: Ludius Latr., Ctenicerus LATR., and many others proposed 
by EscuscHotrz and SrepHens. Comp. Westwoop Modern Classific., 
Generic Synopsis, pp. 25—27, and GERMAR Zeitschr. f. die Entom. 1. 
pp. 241—278, Iv. pp. 43—108, V. pp. 133—192, ke. 
Sp. Hater murinus L., Vort Col. 1. Tab. 44, fig. 26;—-Hlat. eneus L., 
VoeEt ibid. fig. 24; Hater aterrimus L., Panzer Deutschl. Ins. Heft tor, Tab. 
15, &c. The larve of Later (Agriotes Escuscu.) segetis, Hlater lineatus L., 
and other similarly thin and elongated species are sometimes extremely 
injurious; they gnaw the roots of grasses and corn. See on these wireworms 
Kirpy and Spence Jntrod. to Entom. 1. pp. 180, 181, and WerEstwoop, 
Modern Classif. I. p. 238, and the authors there cited. 
Amongst the numerous exotic species we note only Elater (Pyrophorus 
IuuiG.) noctilucus L., Vorr. Coleopt. 1. Tab. 43, fig. 16; it has on each 
side of the thorax a smooth yellow spot; by night it emits a clear light, 
which radiates principally from the spots on the thorax (comp. TREVIRANUS 
Biologie, V. 8. tOO—103, 475). This, with other phosphorescent species (see 
Kirby and Spence Jntrod. 1. pp. 410—412), is found in South America, 
Comp. GERMAR Zeitschr. f. Entomol. 11. 1841, 8s. 1—76, J. CURTIS in 
Zool. Journal, 111. 1828, pp. 379—382. 
[A fine specimen of Hater noctilucus, which had been imported in a cargo 
of logwood, came into VAN DER H@vVEn’s possession after it had lived some 
weeks in other hands. He keptit alive for a fortnight. The phosphorescent 
spots were, in the dark, first blue, then emerald green, then incandescent. 
Large printing could be read by the light, but it was necessary to carry the 
insect along the lines to read continuously. In oxygen gas the luminosity 
was not more splendid. Experiments to determine whether the tempera- 
ture rose with the phosphorescence were interrupted by the death of the 
animal. On dissection, nothing peculiar was observed beneath the spots on 
the thorax, except large or smaller masses of the adipose body connected 
by numerous tracheze. The Professor thinks it not impossible that the 
production of light may not be confined to a particular region, but may 
occur wherever the adipose body occupies the spaces between the organs in 
sufficient mass, and is adequately supplied with air-tubes. The two spots 
on the thorax, though destitute of the brown colouring matter, are of the 
same thickness as the neighbouring integument. Does this thickness, the 
Professor asks, account for the transmission of the green light, whilst that 
which proceeds occasionally from. parts of the’ inferior surface, where the 
membrane is thin, is yellow? However this may be, the adipose body must 
be very unequally phosphorescent, otherwise the light from the under 
