HOLCOGERUS. By Dr. A. Sbitz. 421 



lighter wing-base, tlie Tunisian one witli strong dark markings and the Mauretanian one with scarcely anv 

 markings. When more material of this rare moth is available, one may perhaps be able to separate distinct 

 local forms. A separate genus would then have to be erected, as in the case of Holcoceriis, on account 

 of the strongly divergent antennae. 



C. saharae Lite, is placed into Cossus by the author with a ? As sufficient morphological characters saharae. 

 are not mentioned, nor any reference made to any other species, it is impossible to picture the moth or to 

 say whether it really belongs to this genus. The msect is described as whitish grey above dusted wth grey 

 ui places, with two brownish greyish green bands, one of which is near the margin. Fringes intermixed with 

 greyish brown. Forewing below lighter, bands distmct, placed as above. Hmdwing above and below whitish 

 grey with lighter frmges. Thorax grej^sh brown, abdomen grey, palpi setiform, grey, antemiae dentate. — 

 Oasis of Kebeli (Tunis), m May. 27 mm. 



C. mauretanica Luc. Also unknown to me. Forewuig elongate, with small yellow and dark brownish maure- 

 spots. A curved band runs to the apex. Between veins 1, 2 and 3 a distinct brown patch dentate in the centre, ianica. 

 The reddish yellow spots near the thorax and margins. Underside whitish. Hindwing above whitish dusted 

 with grey. Thora-x yellowish red, abdomen long, grej-ish. Palpi short, white, porrect, tibiae white; antemiae 

 stout, browii. 29 mm. • — One $, October m the Oasis of Kebeli, Tunis. 



3. Genus: Holcocerus Stgr. 



This almost purely Central Asiatic genus, only tMo or three forms of which enter European Russia, 

 is m every respect an artificial group. Several of its forms (about thirty) are quite certainly here ha the wrong 

 place. The species represent all transitions from the Cossus-type inhabitmg tree trunks to those livmg m herbs 

 m the steppes and the desert forms of the genus Paropta. The genus was essentially based on elifferences in 

 the antemiae which, as the name mdicates, appear prolonged, extended ribbon-like, without lamellae on the 

 underside. But the antennae, which in the other families often are of great value in classification, are very 

 variable in the Cossids. In some they are plumose in the ^ (Duomitus), with lamellae (Cossus), anel m others 

 again quite simple (Holcocerus). The lamellae may vary in a genus, bemg quite short (modestus), or of medium 

 length (balcanicus), or very long (terebra, aries), They even vary in specimens of one species, being much 

 longer in the c^ of the African Cossw5 cossus than in that of C. cossus stygianus-o; and they are not even quite 

 the same in $$ of Cossus cossus from the same locality. In one species of Holcocerus — H. pulverulentus Piing. 

 — they are produced into abnormally long ribbons, so that this moth cannot really be placed in any of 

 the present genera. If an organ varies even individually ui a group it is scarcely of any use in characterising 

 a genus, and we shoulel be obliged to arrange species among the C'ossids according to the antennae in an order 

 which would otherwise appear quite unnatural. As was already said with reference to Cossus, the shape of 

 the antennae of the Cossids is probably an adaptation dependmg on whether the food-plants grow close to- 

 gether or far apart, whether the moth inhabits steppes or forests, and whether a prolonged search for the $ 

 is more or less dangerous for the (^. Very little appears to be known of the habits of the Holcocerus; Herr 

 PtJNGELEE, who has described several species, informs me concerning some species which inhabit the steppes 

 that the $$ were often found by "mothing" on the steppes, where they rest on stalks at night. 



H. vicarius Walk. (53el, only the $), has entirely the facies of a Cossus, was also described bj^ Walk- mmrius. 

 ER as belonging to that genus without reference to the antennae, and like most Holcocerus should not be 

 generically separated. Distuiguished by the inner half of the forewing being sharply separated from the hghter 

 outer half; the mottling and striation as in Cossus cossus. On the underside also the dark basal part of the whig 

 contrasts with the lighter striated outer half. — Described from Shanghai, but occurring throughout Northern 

 China, in Tsmg-tau, Aniurland and Japan; appears to be rare, northern specimens somewhat smaller than 

 those from Shanghai and Japan, were lately named tsingtauica Bang-Haas (53 d, as vicarius (J). isinglauica. 



H. consobrinus Piing. (53 b). Undoubtedly allied to the preceding, a transition between it and the cwisobrinus. 

 followmg species. The darker basal area only distmct on the forewing and uidividually very different on account 

 of the variability of the ground-colour, often only recognisable on the underside. On the whole considerably 

 smaller than the preceding msect, but the abdomen of the ^ long and cyluidrical as in that species, not flat 

 with long-hauy sieles as in arenicola. — In Central Asia, perhaps only the Western form of the preceding; from 

 Ili, Kuldsha, Kissil-Jart. 



H. arenicola Stgr. (53 d). Very closely related to the preceding, but the forewuig almost uniformly arenicola. 

 grey, the striae more minute and delicate; abdomen flatter, clothed with dense long soft hair in specimens 

 which are not spoiled by the pressure of the paper. The species of Holcocerus most frec[uently sent home and 

 together with volgensis the only one entering Europe; in the steppes of Southern Russia and Western Asia, 

 extending to Turkestan. As in consobrinus, the ground-colour varies considerably in tint; a very light 

 .specimen with the hmdwing almost white was sent to me by Herr Bartel as ab. albida (53 e). Northern speci- albiaa. 



