290 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



their webs, which are usually spun in well illumined places. They may 

 be regarded as diurnal in their habits quite as much as nocturnal. 



Of Epeira cornuta I examined specimens from Moscow (Russini and 

 Ireland. The side eyes are an amber yellow of a rather dark hue. The 

 middle eyes are still darker; the midfront ones the darkest of all. The 

 side rear eyes have the lightest hue. This species resembles our Epeira 

 strix in its habits, and is much inclined to live in dark places, and for 

 the most part retires to its cell or den, or some secluded retreat, during the 

 day, showing its greatest activity at night. It is not exclusively a nocturnal 

 species, but approaches nearly that habit. 



Of Epeira umbratica I examined two species captured by me upon the 



outer basaltic columns of Fingal's Cave and one from England. The side 



eyes are amber yellow, of a darkish hue. The mid rear eyes 



Epeira have a little darker color, and the midfront darker still. In 



the English specimens the colors were similar, but a little darker, 



the midrear eyes being quite dark and the midfront almost 



black. This species, as is well known, is nearest a nocturnal species of all 



the Orbweavers of Europe. It quite frequently seeks shaded places, although 



this is not its exclusive habit. The webs of the Fingal's Cave spiders were 



exposed to the light, although the individuals were hidden within a little 



recess of the rock. I have seen numbers of the M r ebs of these species on 



the grounds of Tatton Hall, near Manchester, the estate of Lord Edgerton, 



swung between the railings of a rustic bridge, shaded only by foliage. 



These two spiders present the strongest testimony in contradiction of 

 the theory that the white eyes are most useful to those species that are 

 nocturnal in habit. Judging by their habits, their eyes should have been 

 the lightest of any Orbweavers of Europe, but the contrary appears to be 

 the case. I am not able to solve such contradictory facts. Quite at the 

 opposite extreme, and in line with the general tendency, are the eyes of 

 cavern fauna. The eyes of Linyphia weyerii, which I have examined from 

 several specimens received from Luray Cave, are all light colored, the two 

 central eyes being white. 



The above facts appear to point to the conclusion that eyes of a light 

 color are better suited for seeing in the dark, but that dark colored eyes 

 are not necessarily especially valuable to the species having diurnal habits. 

 In short, there does not appear to be a corresponding difference between 

 the nocturnal and diurnal habits of spiders, and the supposed nocturnal 

 and diurnal eyes, sufficiently marked to justify a division on that basis. 



An examination of the above facts also shows that there is a quite 



persistent tendency on the part of the side eyes to be lighter in 



Most color than the middle eyes ; and, of the side eyes, the rear ones 



_ ' are generally the brightest. It also appears that the middle 1 



group of eyes tend to be darker colored, and, of these, the front 



pair are darkest of all. 





