U8 BRITISH LEPIDOPTERA. 



glands as two white dots in Plebeius argus, but does not describe them. 

 The glands are stated to be present in the larva of the European 

 species, Thestor ballus. Anderson says (Victorian Butts., pp. 101-102) 

 that the larvse of the genus Ogyris are greatly attractive to ants, which 

 tend them with great care, never leaving them. He further notes 

 that the pupae of this species are often found in ants' nests, the larvae 

 having pupated there, that the attended larvae are rarely attacked by 

 parasites, but that Ogyris olane, a non-attended species, suffers 

 severely from the attacks of parasitical diptera. Scudder has described 

 the attendance of the ants on Cyanirls psettdargiolus in detail. Perhaps 

 the most remarkable thing that strikes one is that this American 

 species is so close to the European C. argiolus that it might be regarded 

 only as a form of that species, yet the larva of the latter has never 

 been described as protected, or possessed of any traces of the associated 

 structures. The European P. art/us, too, belonging to quite a different 

 section of the Lycaenids, has structures almost identical with those of 

 C. pseudargiolus, and is protected by ants in precisely the same way ; 

 yet P. aegon, in many respects indistinguishable from P. argus, has 

 no such habit, although it has apparently some traces of the structures. 



The actual gland from which the honey is obtained is situated on 

 the dorsum of the larva, and looks like a transverse dorsal lino on 

 the 7th abdominal segment. The larvae of P. argus and others 

 attended by the ants, may easily be detected, owing to there being 

 around them constantly a group of ten or twenty ants. Edwards has 

 detailed how he saw the ants drive off an Anomalun, that would other- 

 wise have attacked a larva of C. pmtdargioliu, so that there can be no 

 doubt that the ants protect the larvas, and in return utilise the sweet 

 secretion exuded from this dorsal gland. 



Eversible glands of an offensive nature are said to be present 

 in some Eucleid larvse. Of these, the so-called "stinging spines" of 

 Doratifera vulnerans are the best known. This species is described as 

 possessing the power to evert eight little tufts of stinging spines, 

 which are concealed when the larva is not irritated. Dyar says that 

 these eversible spines (horns) are hypertrophied warts on joints 4, 5, 

 11, 12 (? 1st, 2nd, 8th and 9th abdominal segments), whilst in /). Icn-ini 

 and D. caxta, the two front ones only are present. These retractile 

 organs consist of a short fleshy shaft with numerous spines, which 

 bend inward over the back, the spines becoming converged, and the 

 whole concealed by a triangular fold of skin. 



Some species appear to have more than one mode of protection against 

 their enemies. The accumulative protection afforded to the larva of 

 Baxilarchia artkcmis, by its colours, tubercles, habits, etc., is narrated at 

 length by Scudder. He says : " Dark and light green and cream colour 

 strive for the mastery, and leave it streaked and blotched, so that it bears 

 no inconsiderable resemblance, in colour at least, to the droppings of 

 some birds, a circumstance which, doubtless, serves it as some sort of 

 protection. Its body is humped, and the bosses bear tubercles, which 

 give it a somewhat repulsive aspect, especially a pair a little behind 

 the head, which are raised aloft, and thickly studded with promi- 

 nences, the effect of which is heightened by the creature's habit of 

 arching this part of the body, bending its head to the ground and 

 raising aloft its hinder part, also studded with roughened processes. 

 Altogether, it is a rather hideous beast. Then, too, if disturbed, it 



