214 



HARDWICKE'S SCIENCE-GOSSIP. 



Glow-worms. — ■ Do they emit heat as well as 

 light ? Can they increase or diminish their light at 

 pleasure ? I have kept some for a month, and their 

 light becomes nightly less brilliant ; they also produce 

 a slight stinging or burning sensation when crawling 

 over the hand. — A. B. 



Spider-killing Wasps. — The following is an 

 interesting extract from a lady's letter, dated Pieter 

 Maritzburg : — "In a corner of my bedroom window 

 a bit of architecture has been going on which has 

 much interested us all. A pair of slender wasps, 

 with golden bodies and purple wings, came and built, 

 bit by bit, most industriously and fast, seven tunnels 

 of clay ; the male insect worked, he fetched the moist 

 pellets of clay from a distant puddle outside the 

 garden. These he worked with mouth and paws into 

 shape most beautifully. When the first tunnel was 

 complete the female went in and laid her eggs at the 

 bottom. Then together they flew away, and came 

 back with a spider, half killed (that is, stung to a 

 deadened state, but so that it would keep and not 

 putrefy), and poor spider was tucked into the tunnel. 

 The pair worked on hunting for spiders all day and 

 popping them in, and night surprised them too soon ; 

 so the male fetched a pellet of clay and made a per- 

 fect door, closing up the hole from all intruders, and 

 they disappeared. In the morning, quite early, I 

 opened the shutter without which they could not get 

 at their work, and very soon they arrived. They cut 

 and tugged at the still damp door, till it came away 

 clear and left the open arch, and several more un- 

 fortunate spiders were added to the larder of the 

 future grub, laid in embryo at the end of the tunnel. 

 Then it was closed with fresh clay, and made doubly 

 secure by an extra thickness of daubing. And 

 immediately, without waiting to rest, another tunnel 

 was built side by side with the first. For days, I 

 think quite a fortnight, we watched their steady work, 

 until seven of these wonderful tombs — or should I say 

 habitations ? — were filled and closed. After the insects 

 had quite finished and gone altogether, leaving the 

 whole daubed together and cemented into one large 

 lump of various shades of clay, I cut it out of the 

 window, and have got it in a basket covered with net, 

 so that we may see the exit of the young creatures 

 that are to eat through all those spiders and break their 

 way into the world some day. I opened one tunnel 

 lengthwise that we might see and count the spiders- 

 there were fifteen in it ! Fat-bodied little garden 

 spiders of various sorts ; one was too big to push in, so 

 they had cut its legs off at the roots ! We waited just 

 a little too long before digging an opening into that 

 wasp's mud castle. What we found was this : a long 

 transparent brown case, and within it a wasp perfectly 

 formed, but colourless. Not a trace of the fifteen 

 spiders ! And these must have been eaten by the 

 little grub which came out of the egg — probably the 

 egg was laid in the fat body of a spider ; and when 

 the spiders were all eaten we can only suppose the 

 grub went through a change and came into the wasp, 

 .but how that beautiful case was formed over it I cannot 

 imagine. You could see the creature inside perfectly 

 as if it were made of glass, and the whole thing 

 exactly fitted the tunnel of clay. After a few more 

 days, another tunnel was opened, not by us, but by 

 the perfected wasp itself. A round hole at the end 

 was cut as if with a sharp instrument, and out walked 

 the pretty creature, slowly and sleepily. Then it 

 walked up on the top of the clay mound and spread 

 its wings in the sun, and looked out at the world quite 

 ready to take its place at once on the business of life. 

 We uncovered the net from the basket and let it fly ; 

 and next season I shall look out for another such 



erection, and open the tunnel earlier, so as to see the 

 grub when half through its larder of cold meat. We 

 saw another and much larger sort of wasp the other 

 day running along with a very large fat caterpillar 

 which it had deadened ; it held it by the head in its- 

 mandibles and the body trailed along under the whole 

 length of the wasp and out behind, and the cater- 

 pillar was so fat that the wasp had to stride along on 

 tip-toe to carry it at all. At last it stopped — left the 

 body a moment, and began like a terrier to scratch at 

 a hole : the loose earth fell away at once, and was 

 evidently only banked up to hide the hole from in- 

 truders. The wasp ran in and disappeared ; presently 

 out he came again, backwards, with some earth which 

 had fallen in ; and he did this several times, throwing 

 out all the earth which had tumbled in. Then he 

 ran and inspected the body of the caterpillar, ran all 

 round it gleefully, and dragged it nearer to his hole. 

 Then we laughed to see the clever fellow, sailor-like, 

 turn himself round and pop down the companion, tail 

 first ; and then peeping out, he reached out his head 

 and arms, and seizing the caterpillar, pulled it down 

 after him, into what seemed a long gallery, leading a 

 great distance. No doubt an egg was laid in the body 

 of the caterpillar for the future grub's sustenance." 



Some common Wading-Birds (p. 152). — Dr. 

 Keegan in his interesting paper on the heron speaks- 

 rather disparagingly of cooked sea anemones, but 

 Mr. P. H. Gosse in his "Aquarium " says that the 

 common sea anemone, A. tnesembryanthemum, when 

 boiled for ten minutes, is excellent eating. — IV. IV. 

 King. 



Louis u'Or. — Can any one kindly tell me the 

 scientific name of the Humming-bird known in the 

 French West India Islands (and possibly also in 

 French South America) as the " Louis d'Or " ? Or 

 can any one refer me to any description of the bird so- 

 called ?— X. 



Birds' Eggs. — Many of the eggs of our smaller 

 birds which have a pinkish tint, owing to the colour of 

 the yolk showing through the partially transparent 

 shell, on being blown become perfectly white (on the 

 unspotted part) and almost unrecognisable by one who- 

 is well acquainted with them in the nest. I thought 

 the eggs would be much better as cabinet specimens- 

 if the colour were restored, and this I have succeeded 

 in doing. I use Crawshaw's scarlet dye, one grain to 

 the fluid ounce of spirits of wine ; this is quite strong 

 enough, and for some eggs, as those of the long- 

 tailed tit, two-thirds of this strength would be 

 sufficient. After having treated the eggs with the 

 corrosive sublimate solution, and allowed them to 

 thoroughly dry, say next day, I wash out the shell 

 quickly with the coloured solution, introduced by a 

 small glass syringe with the point drawn out as fine 

 as possible by means of a blowpipe flame, and remove 

 it as thoroughly and as quickly as possible after the 

 whole of the membrane has been wetted by it. Pro- 

 bably many other of the aniline preparations would be 

 found quite as suitable. The whole of the dye does 

 not dissolve in the spirit ; the colour is very quickly 

 extracted. — IV. G. luxford. 



Ants killing Snakes. — Your correspondent, 

 Y. V. S., will find a very interesting account of ants in 

 the Rev. J. G. Wood's admirable little work, " Strange 

 Dwellings;" also on reterence to "Maundeis' r 

 Treasury of Natural History," under the name of 

 Ants and Driver Ants. For the benefit of the readers 

 of Science-Gossip who are not able to refer to the 

 above works, but whose interest in the subject may 



