Publ. 30. IV. 1913. NOTODONTID^. Introduction. By Dr. A. Seitz. 281^' 



17. Family: Notodontidae. 



The name of the moths which belong here is derived from the lobe-like hindmarginal prominence which 

 is found in many species, and in the specimen at rest projects like a tooth above the back. The family, 

 which contains some 700 species, occurs throughout the tropics and the temperate zones, and is even re- 

 presented m some districts of the Arctic Region. The group is not remarkable for the size of the species; 

 for even the largest Notodonts, which are found in South America, are far inferior in expanse to the giants 

 among the Sphingidae (Cocytius mitaetis), the Satuniids (Attacus atlas), the Noctuids (Thy.sania agriiypina) 

 and, of course, the largest butterflies, and even the largest Cossidae and Hepialidae. 



The development of large forms is not a characteristic of the family, but the occurrence of strange ones. 

 As regards the moths, adaption to the surroundings has often modified the insect to such an extent that 

 the individuals are hardly recognisable as being insects. E. g., if two Pferostoma palpina rest in copula on a 

 small piece of Poplar bark, only an eye specially accustomed to this phenomenon is able to distinguish the 

 pair as such; and whoever collects in foreign countries species with which he is not yet familiar will some- 

 times be obliged to place the specimen into the hand in order to find out if he has to do with an insect or 

 some dead object. The moth of Phalera hucephala at rest resembles so closely a piece of a broken off twig 

 that one only perceives a specimen in its protective position if one already knows the species and bears its 

 picture well impressed in one's memory. 



But adaptation has even more strongly modified the larvae than the moths, the larvae being often 

 provided with means of frightening an enemy. The facies of many species is so transformed as to conceal 

 comijletely the fact that they are caterpillars, and in some genera all gradations in the transformation of the 

 shape of the larvae can be observed. The caterpillar may be quite smooth (Ptero.stoma), or slightly hump- 

 ed on segment 11 (Pheosia), or bear here short points {Lophopteryx); there may be knobs on segment 5 

 (Pygaera) or lateral swellings (Spatalia) or a long process (Notodonta) or a divided appendage {{Hoplitis). 

 The anal end may terminate in a soft fork {Uropyia) or two pointed tails (Gerwra), or bear two long clubs 

 (Stauropus) or a large hump {Hoplitis}. The back of the larvae may be serrate {Nerice, Stauropus), hump- 

 ed (Dicranura) or provided with processes inclining forward (Schizura). Some species have a large head which 

 has no special modifications and is rendered strange only by being held bent back in a peculiar way (Phalera, 

 Lophopteryx), or by being retracted into a sort of hood; in others again the head is surrounded by a kiiid of 

 bonnet, or some nuchal horn-like antlers project above it (Heterocampa). The anal tails sometimes are hardly 

 indicated (Heterocampa), or feebly elevate (Schizura), or jjrolonged and mobile but directed downward at rest 

 (Exaereta), or only strongly prolonged in the young larva (Macrurocampa), or are present in all stages and 

 contain a reversible filament (Dicranura). These terrifying organs serve diverse purposes. The Notodontidae 

 are not protected by inherent qualities, but are in all the stages a welcome prey to the enemies. For that 

 reason are the moths so effectively concealed by their adaptive garb and try the larvae to frighten the enemy 

 by their strange shapes, bluffing him by assuming peculiar attitudes in which the processes and humps be- 

 come very prominent. There are all variations from the simple Sphinx-like attitude (Lophopteryx) to the pro- 

 nounced agressive position of a Dicranura larva. Young caterpillars of Datana perspicua only slightly raise 

 the head, older ones hold, like the Phalera larvae, the whole anterior portion of the body erect and also lift 

 up the tail; larvae of Notodonta and Hoplitis assume a regular zigzag position, and those of Stauropus raise 

 both ends and, moreover, threaten with their long legs. The threatening attitude is often s\i])plemented 

 by active defence. The larvae of Hoplitis bite resolutely and, as may be experienced when removing the 

 eggs of Tachina by an operation, can impart a sharp pinch. Beneath the head of the Dicranura-la.Tva.e there 

 is a transverse slit, similar to that of the caterpillars of Cossus, from which they squirt out for defense for a 

 distance of more than 20 cm a liquid which occasions a burning sensation in the eyes. 



Bright colours are of as little value for an unprotected insect as large size, and are therefore entirely 

 absent from the Notodonts. According to their resting-place among leaves, on tree-trunk.s, halms, etc., 

 the moths are green (Rosema), or of the brown colour of dead leaves (Lophopteryx), or ■ — ■ as is mostly the 

 case — adapted to the tree-trunks (Exaereta, Stauropus, Hoplitis, etc.). The discovery of a freshly emerged 

 Cerura bicusjns closely applied to the bark of a Birch is a master-task even for the ej'es of the best-trained col- 

 lector. Numerous species select the foot of trees as resting-place or sit in the grass, and resemble broken 

 off bits of twigs or chips of wood, e. g. Pferostoma, Phalera and Datana. Among the caterpillars the green 

 protective colouring of the twig or leaf on which they feed is much in evidence (Pterostoma, Pheosia), or they 

 have the brown tint of the branchlet on which they rest (Spatalia). In certain species dichromatism occurs, 

 some specimens being adapted to the green, leaf and others of the same species or even same brood to the 

 brown twig (Pheosia tremula). In other cases the colour can be changed at will for defensive purposes; 

 the larva of Dicranura vinula, for instance, when molested not only shows the two well-known bright purple- 



II 36 



