GENEEATION AND DEVELOPMENT. 201 



seems to think that a kind of hermaphroditism occurs among 

 the workers, and finally decides that the rulers or kings 

 (queens) generate both themselves and the workers, that 

 these generate the drones, and that these generate nothing, 

 but are idle, while the queens remain in the hives free from 

 all unnecessary labour.* 



It is now known that the queen of a hive generates 

 queens, workers, and drones, the workers being normally 

 barren females, and the drones males ; parthenogenesis 

 sometimes occurs. The production of a queen from a 

 fertilized egg depends on the supply of a superior quality 

 of food, called " royal jelly," to the hatched-out larva, 

 and this feeding is arranged by those bees which act 

 as nurses. It is sufficient for the queen to be impreg- 

 nated once only by a drone, for the purpose of depositing 

 vast numbers of fertilized eggs. 



Aristotle very clearly suggested the possibility of herm- 

 aphroditism, and was inclined to believe that it was found 

 in some fishes. He says that if there exists a class of 

 animals which includes females but not separate males, then 

 it is likely that such animals generate from themselves, and 

 that, although up till his time such a question had not been 

 investigated sufficiently to justify a belief, there was some 

 probability that hermaphroditism occurred among some 

 fishes. No males had been seen, he adds, among the 

 Erytlirinoi, but the females were full of embryos ; he had 

 not, he says, found out anything very trustworthy about 

 this.! It seems that he also believed that the fishes called 

 by him Psetta and Channe were hermaphrodite. I 



The researches of Cavolini, Cuvier, and others have 

 proved that hermaphroditism occurs regularly in Serranus 

 scriba, S. cahrilla, and other species of Serranus, and that it 

 occurs in some perches, carp, mackerel, herrings, soles, 

 whiting, and other fishes. Aristotle's Erythrinos, Channe, 

 and Psetta have not been satisfactorily identified, but Cuvier 

 believed that Erythrinos was S. scriba and Channe was 

 S. cabrilla.^ 



A remarkable discovery of modern times is the common 

 occurrence, in Aphis, Cypris, and many other forms of life 

 which multiply with very great rapidity, of parthenogenetic 



- G. A. iii. c. 10, 7596 and 760a. f Ibid, ii, c. 5, 741a. 



I H. A. iv. c. 11, s. 4, vi. c, 12, s. 1. 



S Cuvier and Valenciennes, Hist. Nat. des Poissons, Paris, 1828-49, 

 vol. vi. pp. 179-80. 



