202 



INTRODUCTION. 



fossorial ; tarsi 5-jointed, very rarely 4-jointed ; in certain genera 

 of Scarab^id^e the anterior tarsi are wanting, either in both sexes 

 or in the male only. The structure of the wing-venation is 

 variable in the group, wings being found with the venation of 

 Type II and Type III (pp. 40-42) ; the Cantharidiform venation, 

 however, appears to prevail. 



We have before referred to the concentration of the nervous 

 system and its variability, which is very remarkable. A fall 

 account has been given by Blancbard (Ann. Sc. nat. 3 ser., ZooL 

 v, 1346), and Brandt (Horse Soc. Ent. Boss, tome xiv, 1878, 

 xv-xvii) has deal with the subject in detail. Ganglbauer (Munch. 

 Kol. Zeits. i, 1903, p. 312), quoting from these, says that as 

 regards the nervous system the Lucanid.e are the most primitive, 

 as in these the abdominal chain consists of six or seven separate 

 gauglia. In the Passalid^, according to Blanchard, the abdominal 

 ganglia, as in most of the ScarabyEID^e, are connate, but present 

 a longer complex than is found in the latter ; in the Glaphyrinje 

 (among the Scarab^eid.e) six abdominal ganglia can be traced, 

 but they are approximate; in the rest of the ScARABiEiDiE, 

 according to Brandt, all the abdominal ganglia are united, into one 

 complex with the metathoracic ganglion. In the Geotrupin^e 

 the mesothoracic and metathoracic ganglia approach one another 

 very closely ; iu the CetontiNjE, Eutelin^e, and Melolonthin^; 

 these ganglia are united ; in the Kutelin,e the prothoracic ganglion 

 comes very near to the mesothoracic ganglion, and in the Melo- 

 LONTHiNiE all the ganglia of the thorax and abdomen (including 

 the prothoracic) are narrowed to a simple complex ; the highest 

 point is reached in Hhizotrogus and Laehnosterna, in which the 

 infra-cesophageal ganglion is brought into the same complex. 



The larvae of the group are discussed, and several of them 

 beautifully figured, by Schiodte (Naturhist. Tidsskrift (3) ix, 1874, 

 pp. 227-^76, pis. vii-xix). They are broad, fleshy, whitish or 

 dirty white grubs, and are for the most part wider towards the 

 apex of the abdomen. The head is chitinous and rounded, 

 generally without ocelli ; the antennae are inserted at the sides of 

 the head on a projection which looks like a first joint ; the joints 

 vary in number from two to four ; the thoracic and abdominal 

 segments do not materially differ. The stigmata are conspicuous, 

 and there are nine pairs in all, the first situated at the sides of 

 the prothorax and the other eight in the first eight abdominal 

 segments, in a line ; the legs are comparatively long, with the tarsi 

 very small or only represented by a small claw ; in the Passalid^e 

 the posterior pair is rudimentary ; there are no cerci or anal 

 appendages. In spite of the length of the legs, the larva; have 

 but little power of progression, as the apex of the body is curved. 

 The larva? of the Passalld^e, however, unlike those of the other 

 known Lamellicornia, are active, with a straight body, and the 

 four ambulatorial legs are long, so that they can walk fairly 

 quickly. A few (Cetoniinje) can crawl upon their backs. They 



