COCHLIDIDES (EUCLEHJES). 36B 



armed. Some belonging to the first group have spines of a peculiarly 

 urticating nature. The second are not very dissimilar from those of 

 our European species. The newly-hatched larvae of both groups are 

 without abdominal prolegs, and we can readily understand that the 

 differences observed in the adult forms, are the result of a response to 

 differing stimuli and environment. Dyar says that the Eucleid larvae 

 have, in their most generalised forms, only two rows of tubercles 

 present, the subdorsal and the superstigmatal ; the substigmatal row, 

 present in the Merfalopyt/idae and Pyromorpkidae have here disap- 

 peared. The modification of the tubercles into fleshy horns, and the 

 setaa into urticating spines, have produced the " tuberculated or spiny " 

 group, whilst the reduction and disappearance of the tubercles have 

 produced the "smooth or unarmed" group. The "spiny" larvae 

 have also developed bright and warning colours, whilst the " smooth " 

 larvae are either green or so coloured that their hues aid effectually 

 in their concealment. On the other hand, Chapman has shown that 

 the so-called " smooth " Cochlidid larva, as represented by our Euro- 

 pean species, has a double dorsal row of evaginated spines, placed 

 alternately on successive segments .-.'., and a lateral row on either 

 side of the body, in the first skin (Trans. Ent. Soc. Lond., 1894, 

 pp. 345-347). He has also shown that, in the second skin, these spines 

 become pointed hairs, with an internal tubular structure (differenti- 

 ating them from hairs, though their terminal process may be a hair 

 homologous with those carried by ordinary tubercles), the dorsal ones on 

 abdominal segments now double, i.e., formed of two spines originating 

 close together * ' * * * , and thus completing the double row, of 

 which only the alternate members are present in the first skin. In 

 the third skin the bases of the spines are surrounded by minute spinules, 

 each with a coronet-like apex. In the fourth skin the small spines 

 at the base of the large central ones are less obvious, the whole skin 

 surface being now covered with minute spikelets, whilst there also 

 appear to be some minute glandular structures placed dorsally and 

 dorso-laterally on each segment. With the fifth skin the spines 

 disappear, and the larva now, in reality, becomes smooth. The 

 evaginated dorsal spines of H. cmciata, although arranged first alter- 

 nately and then in a double row, as in C. avellana (testudo), differ from 

 those of the latter (described above) in having two branches. These 

 are fully described later in our account of the species. 



Packard says that the Eucleid larvae are nearly colourless when 

 newly hatched, and that their bodies are more cylindrical than in 

 the full-grown caterpillar. The larvae of the more specialised tuber- 

 culated and spiny genera Adoneta and Empretia (and probably Euclea) 

 have the tubercles already differentiated in the first stage, but the change 

 from the first to the second stage is very great, owing to the develop- 

 ment of large numbers of bristles upon the tubercles, and the gay 

 varied colours and markings of the body. The armature of poisonous 

 glandular spines and the development of bright warning colours are, 

 he considers, evidently characters acquired late in larval life, when 

 the creatures are large enough to attract notice. 



The larvae of the Australian species are, however, the most remark- 

 able, and one of the strangest of these is that of Doratifera vulnerans, 

 figured by Lewin. It is described as having the power to evert eight 

 little tufts of stinging spines, which are concealed when the larva is not 



