Sept., 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



jog 



by its snake-like appearance ; while amons our native 

 species the larva^ of the two elephant hawk moths 

 (Chiuroiampa elpenor and C. (■orcdlns) are striking; instances 

 of a protection gained in a similar manner. 



Like the caterpillars of the lobster moth, those of the 

 elephant hawks are ditlicult to detect when they are at 



Larvie of Euchdia jnrnbtftr. 



home among the leaves of their food plants, owing to 

 their brown — or more rarely green — colouring. But 

 when actually discovered, or when thoroughly alarmed 

 by the rustling of the leaves, the caterpillar draws back 

 its head and the first three segments of its body into the 

 fourth and fifth segments. What then happens is well 



iletfwma themUto. Ex Rio Granda iblack, with "clear" areasi. 



described by Professor Poulton. " These two rings (the 

 fourth and fifth segments) are thus swollen, and look 

 like the head of an animal upon which four enormous, 

 terrible-looking eyes are prominent. The effect is greatly 

 heightened by the suddenness of the transformation, 

 which endows an innocent-looking animal with a terrify- 

 ing and serpent-like appearance." 



This description applies to the C. dpcnor. In the case 

 of C. poncUus the eye spots on the fifth segment, though 

 present, are comparatively inconspicuous. It is a curious 

 fact that these strange markings do not attract particular 

 attention when the caterpillars are quietly at rest or feed- 

 ing. As soon, however, as they asstune their terrifying 

 mask, under the stimulus of apprehended danger, the 

 staring " eyes " — owing to the swelling of the segments 

 as the head and first three body rings are withdrawn — 

 become enormous and prominent. All field entomologists 

 who are familiar with tiiese caterpillars in the wild state 

 are willing to bear testimony to their startling appear- 

 ance when they have assumed their terrifying attitude. 



\"ery similar eye spots, probably of a like protective 

 value, are seen upon the thoraces of certain Central 

 American beetles of the genus Alans. As in this case the 

 markings are delineated upon the hard surface of the 

 thorax they are not really more marked at one time than 

 another. Yet their terrifying apjpearance is enhanced 

 considerably when the beetle assumes the attitude with 

 which it responds to indications of approaching danger. 

 In common with most species of the great " click-beetle" 

 group ( FJateridcrj to which the genus Alans belongs, these 

 insects are capable of folding their legs and antenna' so 



Meliitva m^'satis. 



Ex Columbia. S. A. ired, brown; anterior area « of fore- 

 wings black, spotted whiter. 



closely beneath the body that they are completely hidden, 

 and of remaining perfectly (juiescent in this attitude for a 

 long period of tune. A glance at the accompanying 

 photograph will give the reader some idea of the weird 

 appearance of an Alnus beetle under these conditions. 

 It cannot be said to resemble any other living creature, 

 noxious or innoxious. Yet its appearance is sufficiently 

 forbidding to discourage hostile attack. 



In dealing with the first part of our title we have 

 briefly discussed several insects which are able, at will, 

 to masquerade as something terrible and alarming. They 

 can put on, as it were, terrifying masks, and scare away 

 their would-be persecutors. Bui the protection thus 

 gained is the outcome of bare-faced bluff, and it is con- 

 ceivable that the enemy may one day discover and profit 

 by this fact. Warning liveries, on the other hand, are 

 anything but meaningless bluster. They indicate that 

 the creatures distinguished by them possess certain 

 noxious characteristics which render them unwholesome 

 or unpalatable. 



At the present day, students of entomology accord a 

 fairly general acceptance of the theory of warning 

 coloration as explaining certain extremely strikmg 

 colours and colour contrasts which occur throughout 

 the insect world. In cases of protective colouring, the 



