40 SUMMARY OF CURRENT RESEARCHES RELATING TO 



the same lineage, whether queens or workers, appear to possess a diffused 

 scent which is the same for all the individuals of common descent, and 

 is the means of recognition. The power of recognising this scent is lost 

 if the eleventh segment of the antenna be destroyed. Again, the ants 

 appear to recognise the aura of their own nest by means of the twelfth 

 segment of the antenna. If the eighth and ninth segments of the antennae 

 are destroyed, the ants no longer show any care for the eggs or young, 

 and if the five distal segments are destroyed, they no longer exhibit 

 gregarious instincts. The care bestowed by the ants on the eggs, larvae, 

 and pupae, docs not appear to be essential for the development of these, 

 but if not so tended they hecome overgrown with the mycele of Peni- 

 cillium erustaceum. The author believes that the worker ants feed upon 

 this mould, which they obtain by constantly licking the eggs and young. 

 It does not grow upon the bodies of dead ants, which become covered by 

 Bhizopus nigricans, a mould with spreading hyphae apparently not used 

 as food. 



Macroergates in Pheidole commutata. * — Prof. W. M. Wheeler 

 describes the finding in Texas of nests of this ant which contained the 

 one six, and the other three specimens of very large workers, answering 

 to Wasmann's definition of macroergates. The body was about four 

 times as large as that of the normal workers, and though the total length 

 did not greatly exceed that of the normal soldiers, the enormous dis- 

 tension of the abdomen made the macroergates appear more bulky. 

 They had not however the large heads of the soldiers. Close examina- 

 tion showed that these giant forms contained within the distended 

 abdomen a parasitic Nematode belonging to the genus Mermis. In one 

 case the parasite was fully 50 mm. long, some ten times the length of 

 the ant. The author ascribes the great increase in size of the body to 

 the presence of the parasite increasing the appetite of the host, while the 

 fact that ants feed each other and their larvae renders it possible for the 

 parasitised forms to obtain extra food with ease. Infection must take 

 place in the larval stage. 



Gynandromorphy in a Wasp, f — Franz Friedr. Kohl has found, 

 among a collection of American wasps, a specimen of Ammophila 

 abbreviates F., which has the head and legs of a female, but bears normal 

 mule genitalia at the end of the abdomen. The abdomen resembles that 

 of a female in its robust form, but in the number of its segments, no 

 less than in its genital apparatus, is definitely male. The author is 

 satisfied that the specimen is genuine and is not an artifact. This is the 

 first time gynandromorphy has been described in a wasp. Though the 

 legs are detinitively of the female type, they are slightly stouter in form, 

 and the tarsus bears a few more hairs than usual. Tho case falls into 

 Dalle-Torre and Friese's Group iii. 2, b. 



Female Genital Apparatus in Microlepidoptera4 — Hermann Stitz 

 finds that there are three kinds of chitinous structures round the genital 

 openings, the squamae, the setae, and the spinae. The abdomen in the 

 female consists originally of ten segments, of which the first is aborted 



* Araer. Nat., xxxv. (1901) pp. 877-86. 



t Verb. k. k. Zool.-bot. Ges. Wien, li. (1901) pp. 405-7 (4 figs.). 



X Zcol. Jalnb., xv. (1901) pp. 385-434 (5 pis.). 



