154 



KNOWLEDGE. 



[July 1, 1897. 



to appear is the mason bee [Anthophora), whose "hostile 

 hum " is heard for a moment as it wheels over and then 

 poises at the first opening crocus, sipping the nectar ; then 

 away it goes with a dash, but suddenly pulls up and settles. 

 Note how it sits. It appears to touch the ground with the 

 very tips of its twelve toes, each pair of legs being arranged 

 so gracefully in a moment, the long hairs spreading out as 

 though each one had been combed into position ; and just 

 when you are beginning to realize how wonderful and 

 perfect an insect it is, another bee — a black one— passes. 



Fig. 3. — Twigs of Black CuiTant, showing " Galls." 



and in a moment the russet-brown sitter is up and away 

 in hot pursuit of his mate. At " Happy Hampstead " is a 

 colony of these bees, together with their parasites (Melecta). 

 This parasite has a hoary face and blue-black thorax and 

 body, each segment spangled with patches of intense silvery 

 hairs— the tips of the leg-joints being similarly marked. 

 The beauty of this bee is long remembered ; so is its sting, 



which is long and sharp. A 

 small piece of common wash- 

 ing soda is a useful addition 

 to the stock in pocket of an 

 entomologist, a quick rub with 

 which soothes the pain of 

 either nettle or the sting of a 

 bee. The leaf-cutter bee is 

 to be found in every garden, 

 and may frequently be ob- 

 served cutting out from the 

 leaves of rose bushes and 

 various shrubs, circular and 

 oblong pieces with which to 

 form the bottom and sides 

 of its cells, which are to be 

 found in old posts, under tiles, 

 and between bricks from 

 which the mortar has fallen away — though this bee has no 

 difficulty in removing London mortar, aided by her powerful 

 mandibles. Years ago I used to find a very interesting 



Fig. 4. — Seel ion of Gall 

 showing predaceous Larva. 



Fig. 5. — Destroyer of 

 Gall Mite'. 



bee — AnthiiUum — visiting hollyhocks, first to strip off the 

 woolly covering from the stems, which, when a bundle had 

 been stolen, was carried to its burrow, and used for 

 decorating the walls : then to rob the flowers of the nectar 

 and pollen ; during which pilfering 

 fertilization of the flower takes place. 



There is always a comical side to 

 a London back-garden ; for instance, 

 when we find someone from the 

 country endeavouring to grow black 

 currants. The result is generally 

 failure as regards the fruit. Another 

 drawback to such praiseworthy at- 

 tempts at horticulture is the appear- 

 ance of that "pest," the black 

 currant gall mite (Fig. 1), which 



has the hardihood to venture into a London " back." 

 This mite, though but the four-hundredth part of an inch 

 in length, has become so numerous in (Ireat Britain that 

 many of the black currant orchards in Kent have suffered 

 so much that over fifty per cent, of the crop has been 

 destroyed. 



In form it is not unlike a cigar. Its habit is to ascend 

 the currant trees, and work its way between the scales of a 

 tiny bud, in which it lays an immense number of eggs, 

 which soon hatch, the larvm spreading all over the bush, 

 and ultimately to every bush. Fig. 2 shows a small twig 

 having one healthy shoot, as seen in April, when the 

 delicate leaves are unfolding and the fruit buds are 

 beginning to develop, At the tip and left side are dis- 

 torted buds, having an altogether abnormal appearance, 

 not unlike very minute cabbages ; these are full of gall 



Fig. 6. — Devil's Coach-Horse Beetle taking a Meal. 



mites. The lower " gall " is one of the previous year's 

 growth — perhaps the original one, from whence all the 

 damage emanated. Fig. 3 gives an idea of the appearance 

 of an afflicted bush. This photograph I took in November, 

 and anyone can see how few healthy buds (the sharply 

 pointed ones) are to be found — the " galls " being in the 

 majority. 



Wishing to find " the blessing" (a parasite or predaceous 

 insect), I carefully picked some hundreds of the "galls," 

 putting them in a tin box. I had dissected about one 

 hundred, by cutting them through the centre, before I 

 came upon the object of my search. This was a small white 

 maggot (Fig. 4) between the distorted leaves, feeding on 

 and making short work of the mites. In three months 



