Massart, Versuch einer Einteilung cler nicht-iiervosen Reflexe. 41 



that the bees of the genus Andraena are solitary bees which provide 

 food for their own young- and do not produce neuter females or wor- 

 kers like the hive bees. According to my views therefore the hind 

 legs in the female have been modified by the stimulations involved in 

 collecting pollen for the young, and when the development of the 

 ovaries is arrested the pollen brushes are imperfectly developed. 



It may appear to be inconsistent with this interpretation that in 

 the hive-bee the queen, a fully developed fertile female, is destitute of 

 the pollen basket and pollen brush on the hind foot which are pre- 

 sent in the worker. It might be argued that according to the above 

 interpretation the sterility of the ovary in the worker ought to lead 

 to the absence of modifications for nursing functions, and that these 

 ought to be developed in the fertile queen. The explanation in this 

 case is I believe that the ancestors of the hive bee possessed such 

 modifications and that the queen has lost them through dis use. This 

 effect of disuse has been correlated throughout the evolution with an 

 increased fertility, and in the worker when the functional activity of 

 the ovaries is suppressed the specialisations of the hind limb reappear. 

 The ovary of the worker is not atrophied from the larval stage as 

 in stylopised Audraeua, it is merely prevented from attaining its per- 

 fect development. Possibly if the worker bee were stylopised its pollen 

 collecting adaptations would be suppressed as in the solitary Andraena. 



Although the last case and some others may offer special 

 difficulties, I think the above facts indicate that there is at present no 

 valid objection to the conclusion that in all cases throughout the animal 

 kindoin secondary differences between the two sexes of the same 

 species depend for their perfect development on the presence and 

 normal condition of the primary or essential generative organs, and 

 I maintain that this dependence or correlation is explained on the 

 hypothesis that external stimulations have been the determining causes 

 of the secondary characters, but is not explained on the hypothesis 

 that the said characters have been determined exclusively by the pro- 

 cess of selection from variations arising in the germ and independent 

 of external stimulations. [105] 



Versuch einer Einteilung cler nicht-nervosen Reflexe. 



Von Jean Massart, 



Professor an cler Universitat Briissel, Assistant am botanischen Institute. 



(Fortsetzung.) 



IV. Art der Reaktionen. 



A. Vorbereitende Reaktionen oder Tonus. Jeder Organis- 

 mus ist Zeit seines Lebens Sitz einer unausgesetzten Thatigkeit, von 

 der jede AeuBerung eine Reaktion auf irgend einen Reiz darstellt. 

 Die groben sinnfalligeu Reaktionen, die einzigen, welche der Beobach- 



