Entomological Society. 4275 



doubt of the Paraguay worm being identical with, or at all events nearly allied to, that 

 which J obtained at Minas. 



" There cannot be a doubt of this larva being that of some Coleopterous insect, 

 but of which it is impossible for me to say. It seems probable that the strong phos- 

 phorescence does not entirely cease with that stage, even although it should become 

 more or less modified afterwards ; and it may therefore be hoped that the property 

 may lead to the discovery of the perfect insect. But although I have been collecting 

 the Fauna of that part of the Brazils inhabited by this larva, through all seasons and 

 on a somewhat large scale, yet have I never met there with any other luminous insects 

 than Elateridae and Larnpyridse. To the larvae of the first of these families it has 

 no resemblance ; but it undoubtedly has several features in common with the latter, 

 and on the whole it has a stronger affinity with these than with any other form of 

 larva with which I am acquainted ; and yet, as will be seen from the subjoined de- 

 scription, it differs from the larvae of the three principal genera of the family in some 

 essential points : so that it still remains a question whether the perfect insect will be 

 found to belong to the Lampyridae. 



" Description. — My specimen was a little smaller than Azara's, and measured 40 

 millim. in length, and about 5 millim. in breadth. Body flattened in such a way that 

 the dorsal side is slightly arched, and separated by a margin from the more flat abdo- 

 minal side. Hairs are scattered all over the body, but more sparingly on the upper 

 than on the under side, and especially towards the edge, where they stand so close to- 

 gether as to give that part a villous appearance. The colour above is a dirty reddish 

 brown, below yellowish white. The head is horny, protruding somewhat horizontally, 

 without admitting of being retracted and hidden by the first thoracic segment: there is 

 a sharp fold around it, which gives the anterior part an appearance of extending from 

 the hinder portion as from a sheath, and conceals the articulation of the lower parts of 

 the mouth : on each side is one eye only, though rather large, placed inconsiderably 

 before the fold just mentioned, and directed laterally and somewhat forward : before it 

 are the palpi, which consist of four joints, the outermost being very short, and much 

 thinner than the preceding ones. The structure of the mouth seems to indicate that 

 the larva is of predaceous habits, which agrees also with the nocturnal life it appears 

 to lead. The much-curved jaws are thick at their base, becoming rapidly attenuated 

 tow r ards their tips, without being terminated by a fine point ; on their inner margin 

 they bear only a small knob or obtuse tooth, and, when closed, they cross each other 

 at the apex. There is an upper lip between the jaws, hardly large enough to fill the 

 entire space between them, and therefore easily overlooked ; its outer margin has a 

 slight incision in the middle. The lower parts of the mouth, the jaws, and the under 

 lip, are grown together with the extraordinarily developed basal joint, into a large 

 plate, on which two deep furrows alone point out the limits of the lip and jaws : from 

 the anterior margin of this plate, quite towards the sides, originate the maxillary palpi, 

 which are cylindrical, short in comparison with their considerable thickness, and con- 

 sist of four joints, the outermost being terminated by a slightly arched, cutaneous, and 

 soft lamina, strongly contrasting with the other (brown) part by its whitish colour: 

 close within these is the two-jointed maxillary lobe, almost concealed by the palpi, 

 which are many times larger ; and in the middle is seen what I think is properly the 

 tongue, which is narrowest at its origin, widening towards the insertion of the two- 

 jointed lingual palpi, and protruding between these with a little triangular elongation, 

 bearing two brushes at its apex. There are twelve joints in the body, besides the horny 



