6866 Insects, 



the spirit, which was very rapid with the tubes, is almost prevented. 

 The bottles are not ranch more expensive, and, as the shoulder need 

 be but very slight, the mouth of the bottle will still be of sufficient size 

 to admit of almost as large a spider as the body of the bottle can well 

 contain. Up to this season the nature of the ground I have searched 

 (wood and heath) has made sweeping and beating the successful modes 

 of looking for spiders, but this seasftn these methods have been im- 

 practicable on the sand hills, an^ong short herbage and coarse star- 

 grass. Among these I have had io go on my knees and separate the 

 grass and rubbish, when a living world, both of spiders and beetles, 

 has generally been laid open. 



O. Pickard-Cambridge. 



Errata— Zoo}. 6497, /or Cespiticola read Cespiticolis ; p. 6499, for Pholeus read 

 Pholcus ; p. 6501, /or extansa read extensa ; and same page, for Enocvlisa read 

 Senoculina. — O. P.-C. 



Double-hroodedness. — The following is a description of the larva of Hemerophila 

 abruptavia : — Ground-colour clay-brown mottled with faint green, slightly rugose. 

 Head whitish. From the head proceed, as far as the third segment, three dark lines. 

 The two outer ones are bordered by a clay-coloured line, which extends to the anal 

 segment. In the space formed by these lines are twelve triangular dorsal marks, the 

 apices of which meet down the middle of ihe back. On the anal segment is a black 

 ring. The ground-colour is sometimes chocolate-brown, the markings being barely 

 discernible. Length H inch. Food, privet. The above description is taken from 

 larvae alive at the present moment. This latter fact induces me to make a few- 

 remarks upon the question of double-broodedness. I am not aware that H. abruptaria 

 is considered to produce two broods in the year. The longer I investigate this 

 question (and I have done so with great care the last two years) the more satisfied I 

 am that some insects, in one sense are, and in another are not, double-brooded. By 

 double-brooded, in its strict signification, I understand eggs to be hatched, say, in 

 April ; these produce perfect insects in the summer ; in their turn they lay eggs ; the 

 larvae produced from them feed up and become pupae some time in the autumn, and 

 all the insects emerge the same year. In such a case I understand an insect to be 

 double-brooded in its strict sense. But there is another kind of double-broodedness, 

 which 1 term partial ; i.e., eggs are laid, as before, in the summer; these become 

 pupae in the autumn ; but only three or four, sometimes only one or two, perfect 

 insects appear that year, the remainder passing through the winter in that state, and 

 emerging in the following spring. Assuming my first definition to be correct, I still 

 adhere to the opinion T have expressed on former occasions, — that many insects 

 termed double-brooded are not so, e.^., Notodonta dictaea, N. camelina, N. ziczac, 

 Ptilodonlis palpina, &c. Like those who differ from me — viz.^ Messrs. Crewe, Gas- 

 coyne and others — I have paid great and increasing attention to this matter, especially 

 since I came into Derbyshire, where (at least in my locality) the dearth of insects is 

 so great that I have had ample time to devote myself more particularly to the investi- 



