558 RECORD OP CURRENT RESEARCHES RELATING TO 



with imprisoned ants, but is probably not so great in a state of nature. 

 No doubt, with ants, as with men, an artificial condition of society 

 gives an inducement to a larger devotion to personal appearance. 

 Invariably at nigbt, when the gas-lamp is lit and placed near the glass 

 formicaries, the heat and light, both of which appear to be grateful to 

 them, tempt them out, and they begin operations. So also after 

 eating and when awaking from sleep. In short, whenever they are in 

 a particularly comfortable state, they express their satisfaction by 

 making their toilet. 



Malformation in an Insect.*— Dr. H.Dewitz describes a larva of 

 Atta insularis, in which the last leg on the left side, instead of lying 

 beneath the larval cuticle like the other five, projected through a hole 

 in the cuticle, its last four joints being exposed. The aperture 

 through which extrusion had taken place had been formed by the 

 partial detachment of an ellipsoidal sbred, which remained attached 

 along the outer side of the aperture like a valve. Both this valve and 

 the edge of the aperture were strongly chitinized. 



Parasitic Insects. f — Dr. Gurlt gives a new list of vertebrates 

 (76 mammals and 519 birds), on which various species of parasitic 

 insects live ; the name of each host being followed by those of its 



Notes on Phryganeae.^ — Fritz Miiller, writing from Brazil, makes 

 some remarks upon this group, first stating that he has found (rudi- 

 mentary) persistent tracheal gills (as in Pteronarcys) in one species 

 (? Tetracentron), while in another these gills were cast oif at the 

 assumption of the imago condition. The same imago had on the 

 anterior edge of the third to the sixth rings of the abdomen peculiar 

 processes, which were absent from the remaining somites ; on the end 

 of the fifth ring there were also two dark chitinous plates. All these 

 structures, quite useless to the adult insect, are the persistent remains 

 of tooth-like plates, so strongly developed in corresponding positions 

 in the larva, and assisting it in creeping in and out of its tube. The 

 insect in question, therefore, aifords an example of two kinds of rudi- 

 mentary organs ; first, organs inherited from an adult ancestor to whom 

 they were of use ; and secondly, organs having reference only to the 

 larval condition, and subsequently transmitted to the adult. 



The pupa of a species of Bhyacophila, the larva of which lives 

 amongst the branches of Podostema, has well developed claws ter- 

 minating the first and second legs. These are useful to the insect as 

 it creeps through the tangled branches of the plant. 



According to the characters of the pupse, the IricJioptera may be 

 divided into two groups : in one {Rhyacophilidce and Hydropdlidce), the 

 larvfe are quiescent in closed webs ; in the other (LeptoceridcB, Serico- 

 stomidce, Hydropsy chidce, Linmophilidce, and Phryganidoi), the webs or 

 cases have an opening at each end, through which a stream of water, 

 due to the movements of the pupa, is constantly passing. 



* 'Zool. Anzeiger,' ii. (1879) p. 134. 

 t * Arch. f. Naturg.,' xliv. (1878) p. 1C2. 

 X ' Zool. Anzeiger,' ii. (1879) p. 283. 



