ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 577 



during the metamorphosis by " regeneration-crypts," which are formed 

 during embryonic life, and in the larva take on a characteristic flask 

 shape. The author is not able to throw any new light on the question 

 of the origin of the musculature of the gut of the imago. 



Fungus-collecting- Ants.* — Prof. G. v. Lagerheim has studied the 

 habits of Lasius fuliginosus Latr. which occurs in Sweden and cultivates 

 Septosporium myrmecophilum. The point of interest is that the motive 

 appears to be different from that in the other known cases, for there is 

 little evidence that the fungus is useil to any extent as food. The ants 

 build their nests usually of rotten wood, at times also of particles of 

 earth, sand, &c. The particles are fastened together by means of a 

 secretion, but the walls so formed are also interpenetrated by fungoid 

 hyphge, which ramify through their substance aud appear to give stability 

 to the whole. In addition to these " intramural " byphaa, thu fuugus 

 also appears as a down-like coating on the surface of the wall. The 

 evidence as to intention on the part of the ants is based on the fact that 

 the fungus occurs as a pure culture, unmixed witb other genera, and that 

 it always occurs in the nests. The purpose would appear to be to give 

 stability to the walls, but this applies only to the intramural hyphae ; the 

 object of the extramural coating may be to serve to some extent as food, 

 perhaps it also roughens the walls and so affords the ants foothold. 

 The fungus must depend for food chiefly upon tbe mortar-like secretion 

 by means of which the particles of the walls are fastened together. 



Life-history of Plant-lice.j — R. Thiele notes that in July Aphides 

 sometimes appear suddenly on trees previously free from them, a fact 

 which he explains in the following way. In June, or the beginning of 

 July, in the colonies of wingless forms winged females may appear, 

 which on perfectly calm days may be seen in the air as white specks. 

 These produce viviparously fifteen to twenty females which are fertilised 

 when born, and are capable of giving rise to new colonies. These 

 fertilised females are furnished with a suctorial proboscis. 



Farthenogenetic Origin of Drones.* — Wilhelm Paulcke has re- 

 investigated this much debated question. He has examined newly 

 deposited eggs from worker-cells and from drone-cells, and also the 

 eggs laid by workers (substitute-queens) in Apis mellifica. In 800 

 drone eggs he found what appeared to be a sperm nucleus in three 

 cases only, and never found the characteristic sperm radii which regu- 

 larly occurred in the worker eggs. In tbe eggs laid by workers there 

 was neither sperm nor sperm radii. In the drone eggs he found four 

 chromatin groups ; of these two seem to be the result of the division of 

 the first polar body, one represents the second polar body, the fourth 

 is the egg nucleus. The results therefore generally confirm those of 

 Blochmann. A more detailed account of the research is promised. 



" Cuckoo-spit." § — Max Gruner has investigated the function, origin, 

 and composition of the frothy secretion with which the larvae of Aphro- 

 pliora and Philsenus invest themselves. Experiments convinced him 



* Ent. Tidskrift, 1900, 13 pp. See also Bot. Centralbl., Ixxxii. (1900) pp. 334-6. 

 t Zeitschr. Pflanzenkrank.. ix. (1S99) pp. 260-2 (I pi.). See also Bot. Centralbl., 

 Ixxxii. (1900) pp. 345-6. t Anal Anzeig., xvi. (1S99) pp. 474-6 (2 figs.). 



§ Zool. Anzeig., xxiii. (1900) pp. 431-6. 



