July 1, 1897.] 



KNOWLEDGE. 



153 



LONDON : JULY 1, 1897. 



CONTENTS. 



The Insects of a London Back-Garden.— II. Bv Fred. 



Knock, F.L.S.,r.E.S. (Illustrafed) 153 



Bird-Songs in Summer. Bv Chaeleb A. Witchell ... 157 



Jubilee Honours 158 



The Threshold of a New Era 158 



On the Vegetation and Some of the Vegetable Pro- 

 ductions of Australasia. — III. By W. Bottixo 



Hbmslkt, F.R.S.,F.L.S. (Ii/jM<ra<ed) 161 



Letters:— T. W. Backhofse ; W. H. S. Monck; Jas. D. 

 Haedt; Alex. B. McDowall; W. Alfred Pahb; A. W. 



BtrSBEIDQE 164 



Science Notes 167 



Notices of Books 168 



Shoet Notices 169 



Books Eeceited 169 



The Hourglass Sea on Mars. Bt E. M. Antoniadi 



(Illtisfrafed) (Plate) 169 



The Language of Shakespeares Greenwood. — II. By 



Geobge Moeiet 172 



The Face of the Sky for July. By H. Sadlbb, F.R.A.S. 174 



Chess Column. By C. D. Locock, B.A.Oion 175 



THE INSECTS OF A LONDON BACKGARDEN.-II. 



By Fred. Enock, F.L.S., F.E.S. 



IN all probability on the willows forming the back- 

 ground of our " thirty feet by seventeen feet " will 

 be found several larva of the common puss moth, 

 the eggs of which are generally laid singly on the 

 upper surface of the leaves, reminding one of 

 miniature macaroon biscuits. The baby caterpillar 

 emerging from these eggs is velvety black, with two long 

 whip-like tails which are telescopic, each containing a 

 long, red, thread-like addition, which is rapidly shot out 

 and whisked about from side to side whenever any 

 ichneumon &j endeavours to come too near. Although 

 these parasites are persistently whipped off, there comes 

 a time of weakness of body when the grub is putting 

 together a new suit of clothes, which are put on under the 

 old ones ! At such times the wary ichneumon takes the 

 opportunity for settling on the back of the larra, and 

 although it has an uncomfortable time it manages to 

 pierce the double skin, and insert several of its eggs 

 within the body of the unfortunate puss moth larva. 

 With so many uninvited guests, literally eating the host 

 out of home and body, what else can l)e expected than 

 ruin to all hopes of ever changing to a lovely puss moth ? 



The noble caterpillars of the poplar and eyed hawk 

 moths are frequent visitors to our gardens, as well as 

 the more beautiful Sphinx ligxtstri — the privet hawk moth. 

 It is the first sight of such "big game" as these moths 

 that fires the youthful imagination ; but so much has been 

 written of these grand insects that I will only take one 

 more example of Ijepidoptera which I have found in my 

 " thirty feet by seventeen feet." 



Some years ago a large number of that ancient Roman 

 dainty, the Cossus of Pliny— or, as we so well know it, 

 the larva of the goat moth — appeared in the kitchen, 

 much to the amazement of our domestic, who, from the 

 power of example, did not put the grubs into the fire, 

 but shovelled them up and submitted them to my notice. 

 Some of them were three inches long 

 and as thick as one's middle finger — 

 the colour " yellowish flesh," with livid 

 blotches on each segment. For more 

 than a week we had daily visits from 

 these " dainties," until at last I decided 

 to examine a small willow growing in 

 the garden of our next-door neighbour. 

 I soon saw that the trunk, four inches 

 diameter at the ground, was simply full 

 of these larvce, of all sizes from two to 

 almost four inches in length. I broke 



the trimk down and up ; the total 



number of these foul-smelling grubs fkj. i.— Black 

 taken from out of the trunk, together Currant Gall Mite, 

 with those which had climbed and 

 excavated the wall, was just one hundred and five ! 



These larva do a great deal of damage to willow and 

 oak trees, from the day of their birth, when the tiny grubs 

 eat their way through the bark, under which they pass 

 their childhood, until, increasing in size and age, they 

 go deeper and deeper and completely riddle the largest 

 trees with holes half an inch in diameter. Their relative, 



the wood leopard moth, 

 is even more destructive, 

 the larvm boring up into 

 the smaller branches. 

 This is the cause of the 

 death of many a tree 

 in and around London. 

 Years ago, thirty or 

 forty ash trees, of about 

 the same number of 

 feet high, along the 

 Hanley Road, N., were 

 terribly infested, and 

 on one day in July I 

 "swarmed" up one of 

 them and took twenty- 

 two female wood leopard 

 moths which had 

 emerged that afternoon. 

 Not having a box with 

 me, though plenty of 

 pins, I stuck all the 

 specimens into my box 

 hat and on my coat — 

 much to the wonder of passers-by, who had doubts of my 

 sanity. Such doubts are still shared by many even now, 

 for where strange insects are accessible, there I feel it my 

 duty to be ; and, after all, Mrs. Grundy is quite welcome 

 to her ideas. 



Now, we cannot live long in a London " back " without 

 becoming aware of the music of the humming bee or bees — 

 for various kinds favour us with their presence. The first 



Fig. 2 —Twig of Black Currant 

 in April. 



