406 C. H. TURNER 



mit the formation of images, one is justified in assuming that 

 that spider saw the female in front of which he was standing. 

 But this does not warrant the assertion that all species of running 

 spiders behave in the same way. Montgomery ^' admits that 

 in the attids and in the tycosids sight plays a considerable part 

 in sex-recognition; but holds that it plays no such role in other 

 spiders. He contends that touch plays the most prominent 

 role in sex-recognition of spiders, and he records observations 

 in support of his contention. Granting that Dysdera crocata 

 has visual images, it must also be admitted that the experiment 

 described by Petrunkevitch does not warrant the universal 

 statement made by him. 



Graenicher ^® has furnished statistics, compiled from obser- 

 vations made by himself in Milwaukee, Wisconsin, and by 

 Robertson in Carlinville, Illinois, which demonstrate that 

 the behavior of our American bee-flies (Bombyliidae) towards 

 colored flowers is entirely unlike that of the European bee-flies. 

 Herman Mueller claims that the bee-flies of Europe show a 

 pronounced color preference for red, purple, and blue as opposed 

 to yellow and white, x^bout seventy-one per cent, of the visits 

 of the American bee-flies were to white and to yellow flowers. 

 These visits were made by eighteen species of bee-flies to fifty- 

 two species of flowers belonging to seventeen families. The 

 short-tongued bee-flies of Europe avoid flowers with concealed 

 nectar; the short-tongued American forms make more visits 

 to such flowers than to other kinds. Evidently the author 

 believes that vision plays only a minor part in the life of these 

 flies, for he writes.: " Structure of flower, odor, taste, and supply 

 of nectar determine probably more than anything else the 

 extent to which a flower is attractive to such an insect." This 

 pronounced difference in the behavior of related species in the 

 same climatic zone furnishes a problem for the ecologist. 



2. Hearing. — After reviewing the literature on the subject, 

 Montgomery '^ concludes that there is no evidence that spiders 

 possess the sense of hearing. Some spiders have stridulating 

 organs, and in some cases these are confined to the males; but 

 no tests have been performed demonstrating the spiders' re- 

 sponse thereto. 



3. Towc/z.— According to Montgomery " touch is the dom- 

 inant sense in spiders and seems to be the special function of 



