Manchester Memoirs, Vol. Ixii. (191 7), No. 2 9 



number of chromosomes, while the egg's of the sexual race 

 (Artemia univalens) maturate in the usual manner. 



It thus appears highly improbable that Brauer's account is 

 correct. 



Ants, Bees, Wasps. — Petrunkewitsch (1901) studied the matu- 

 ration divisions of the unfertilised eggs which give rise to- the 

 male Honey bee, and showed that two polar bodies are pro- 

 duced, the first division being the reductive one. He further 

 asserted that after the production of the polar bodies the inner 

 half of the first polar nucleus fused with the second polar nucleus 

 to form a single one. The female pronucleus migrated inwards 

 and the outer half of the first polar body degenerated. The 

 nucleus formed by the fusion of portions of the polar bodies gave 

 rise to the male germ cells by subsequent divisions. 



The number 01 chromosomes in the original nucleus before 

 maturation was sixteen, after the formation of the polar bodies each 

 nucleus had eight chromosomes, and the original number was 

 reformed in the male germ cells by the fusion of the products of 

 maturation. As the somatic cells lare developed from the female 

 pronucleus, which contained only eight (chromosomes, the normal 

 number, sixteen, was produced by aj further division of the 

 chromosomes, which on this occasion dad not separate from one 

 another. 



This sOimewhat fantastic hypothesis was not disputed until 

 1904, when Meves published a short note, followed by more 

 detailed work in 1907. 



Meves attacked the problem by studying the maturation of 

 the germ cells of the male bee. He first showed that the number 

 of chromosomes in the queen bee is thirty-two, and not sixteen, 

 as Pietrunkewitsch supposed. The spermatogonial cells of the 

 male contain sixteen chromosomes, that is, half the normal 

 number. At the first maturation division the chromosomes appear 

 as eight long double rods, which shorten and thicken; the result 

 of division is not two cells, each with eight chromosomes, but 

 one large cell containing eight double chromosomes and a small 

 enucleate bud at the top of the spermatocyte. 



At the second division the chromosomes divide equationally, 

 but instead of forming two functional cells, which will develop 

 into spermatids, only one functional cell with eight double 

 chromosomes is produced and the other ceil degenerates. Thus, 

 as a result of maturation, only one spermatozoa instead of four 

 is developed from each spermatogonium. 



In 1908 Meves published the result of investigations on the 

 Hornet. Here the first spermatocyte division is similar to that 

 of the bee, but the second division, on the other hand, results 



