December 25, 1903.] 



SCIENCE. 



831 



effects of a brilliant theory like that of 

 Dzierzon, backed by the weighty argumenta- 

 tion of a von Siebold, and the way it Hatters 

 our ineradicable tendency to formulate, con- 

 ceptualize and schematize in advance of all 

 exhaustive study of nature's processes.* 



I find the following observations on a 

 fungus-raising ant, the ' Sauba ' {Atta 

 cephalotes) of Trinidad, recorded by Tanner:f 



My 'B' nest had neither queen nor male when 

 it was set up on the 4th July; a few larva; and 

 pupa; were put into the nest at starting. The 

 last of these became an ant on the 14th August, 

 41 days after eapture. 



The first eggs were seen 1!) days after the cap- 

 ture, viz., on the 23d July. Veiy many small, 

 medium-sized and large ants were matured from 

 these eggs before its [tlie nest's] destruction on 

 the 6th November, in periods of from 57 days for 

 the smallest to 74 days for the larger ones. On 

 the 20th October a male was matured, on the 3d 

 November there were 25 males. On the 2d Xo- 

 vember a queen was matured, and another on the 

 5th, three days later, and their period was about 

 84 days. Thus, there are about 10 days for the 

 egg, as a larva it varies from 27 days for tlie 

 smallest workers, 44 days for the ordinary work- 

 ers and 54 for males or queens and 20 days for the 

 pupa stage. * ♦ • 



It is, therefore, as far as this experiment goes, 

 conclusive, that workers, taken as these were 

 from a nest wliich had been living in community 



* Absence of critical caution in accepting the 

 Dzierzon theory is seen, for example, in works 

 like Castle's ' Heredity of Sex," when the author 

 makes the following apodictic statement (p. 

 191 ) : ' That the spermatozoon also bears sex is 

 manifest in the case of animals like the honey- 

 bee, for the egg of the bee, if unfertilized, invari- 

 ably develops into a male, but if fertilized into 

 a female. Professor T. H. ilorgan, in his re- 

 cent work, ' Evolution and Adaptation,' pp. 424, 

 425, makes a similar statement: ' In the honey- 

 bee all the fertilized eggs produce females and the 

 unfertilized eggs males'; although he proceeds 

 to cite the conditions in an insect of the same 

 natural order as the bees and ants, namely 

 the currant-fly (.Yt/iiufus rihcsii), which may, mi- 

 der certain ccmditions, prmluce both males and 

 females from parthenogenetic eggs. 



t (Ecudotiia cephalotes. Second paper. Trini- 

 dad Field Naturalists' Club, Vol. I., No. 5, De- 

 cember, 1892, pp. 123-127. 



witli males, do lay eggs, and that fnnii tlu'iii lUey 

 can produce males and queens. 



Tanner's observations go to show that the 

 eggs of Atta cephalotes workers may give rise 

 to ants of all three sexual forms, that is, males, 

 females and workers of the different castes so 

 remarkably developed in these large fungus- 

 raising ants. The implication in the last 

 quoted paragraph, that the production of all 

 these forms depended on the fertile workers 

 having come from a colony containing males, 

 ma.y be gratuitous {vide infra). 



More important observations on this sub- 

 ject have been recently made by 11. Reiehen- 

 bach, a very conscientious worker.* 



I quote his results in full : 



In the spring of 1S09 I pUued in an empty 

 artilieial nest of the Janet pattern eleven workers 

 of Lasius viger L., more for the purpose of show- 

 ing my pupils the commonest of ovir ants, than 

 for the purpose of conducting definite observa- 

 tions. I fed them with invert sugar and hashed 

 meal-worms. Even after a few days 1 noticed 

 several packets of eggs which had been laid by 

 the workers. This was nothing new to nie, and 

 1 expected that to ha])|ifii wliiili had happened 

 in my other colonies, iiaiiiily. tliat the larvie 

 liatching from such eggs wonhl huecnmh to the 

 cannibalism of the ants. At most I supposed 

 that I might obtain males, since it has long been 

 known that males arise from unfertilized eggs 

 laid by workers, as in the case of the honeybee 

 and the social wasps. 



But to my astonishment, the larva' piq>atcd 

 and produced typical icorkcrs, which agreed with 

 their progenitrices even in size. A few days 

 later they had acquired their mature coloration 

 and began to take part diligently in the labors of 

 the colony. 



Thus it is possible that irorkcrs may drrclop 

 from unfertilised eggs laid by irorkers. 



A little later the number of egg-packets in-, 

 creased, and towards the end of Jmie the num- 

 ber of workers had risen to over a huiulre 1. and 

 a number of larva; and pupx were being busily 

 carried about, assorted, fed and licked; the ants' 

 appetite was excellent, the glass manger was 

 found licked clean every morning; pupa-cases, 



* ' Ueber Parthenogenese bei .Anu-isen und 



andere Beobachtungen an Ameisenkcdonien in 



kiinstlichen Nestern,' Biul. Cnitnilhl.. 22. Bd., 

 1002, pp. 461^65. 



