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course, sub-divided. This plan of Berthau is an attempt to solve the spider 

 classification diflBculty, but it has been severely criticised by Professor Thorold. 

 The plan of arranging spiders according to the structure of their webs must be 

 open to severe work and study before much progress could be made. Surely it is 

 a difficult matter to detect a spider's web very often. I used to pass under a 

 doorway many times before discovering that a web was in the corner of it, and yet 

 there it was. That web supplied me with one of my best slides, and I injured it 

 two or three times before getting just what I wanted. If this was so invisible to 

 me at times when looking for it, how much more difficult would it be for those 

 who did not know of its existence. It is often impossible to see a spider's web — 

 you detect it by its crossing your path : and are sure of its presence by its being 

 in your way. Professor Thorold tnakes a classification of spiders and divides 

 them into sedentary and wandering. The sedentary are those which capture their 

 food by means of snares, and do not move much from place to place for their 

 prey ; whereas the wandering are those which obtain their food from trees, water, 

 or the ground. This may be a good system ; it is certainly one of the very latest as 

 to time, but it would be to a beginner, I should think, very difficult, from the fact 

 that a young student could not possibly know, without much study, a sedentary 

 from a wandering spider. Dahl classifies spiders according to the character and 

 placing of the auditory hairs on the limbs of spiders. He divides them thus : 

 1. Tibia — with two series of auditory hairs ; meta-tarsus with one hair, and 

 tarsus without hairs. 2. Tarsus — without depression of the.se hairs, generally 

 bearing hairs like the meta-tarsus and tibia. These are sub-divided according to 

 the presence of one or two series of auditory hairs on the tarsus. For this 

 summary I am indebted to the Journal R.M.S. for 1884. This classification is 

 scarcely likely to find general acceptance. It is put in here to show what great 

 difficulty there is in obtaining a satisfactory scheme to make spider study easy. 



The plan which seems to me a good one, for arranging the genera and 

 species of spiders, is that of our countryman Mr. Blackwall. He takes the eyes 

 as the standard, and, although the eyes are said not to be alwaj's uniformly 

 persistent in number, yet the plan seems a good one. All of them have eyes, and 

 the eyes can readily be discovered by anyone looking for them. He makes his 

 spiders to be classified under the two divisions — Octonoculina, or eight eyed, and 

 Senoculina, or six eyed. General Hobson made a shield, by means of which he 

 was able almost at a glance to tell to what genus a spider belonged. He found 

 out the number of the eyes first ; then, by means of a moveable index which 

 contained the words Family, Genus, Abdomen, Breastplate, Cephalothorax, &c., 

 he was able to refer the creature to the shield which contained the peculiarities of 

 all the species. For ingenuity, this thing is not only a royal road to the study of 

 spiders, but it shows an amount of skill rarely to be met with. In the circle most 

 remote from the centre, he has drawn from Mr. Blackwall's spiders the peculiar 

 positions of all the genera of our British spiders. There is only one more classi- 

 fication of spiders with which I am acquainted. It is based entirely upon the 

 Vulva, and is not at all pleasing to think or hear about. Of one thing we may rest 

 assured, that whilst spiders are differently classified by various writers, yet their 



