STREPSILAS. 



72$ 



points in the economy of the Strepsiptera, respecting 

 which information or confirmation is required. 



1. What are the sexual distinctions in these 

 insects ? 



2. In what manner and at what period of the year 

 does the fecundation of the female take place? 



3. At what period of the year are the eggs de- 

 posited ? 



4. Are they deposited separately in the cell of the 

 wasp or bee, or are they laid in the eggs of those 

 insects, or within the larva, pupa, or perfect insect? 



5. How long do they remain unhatched, and do 

 they lie in that state until the larva of the insect 

 attacked has attained its full-growth, or assumed the 

 pupa state ? 



6. How long do the larvae of the Slrepsiptera re- 

 main in that state ? Do they cast their skins ? In 

 what manner do they feed ? 



7. How long do they remain in the pupa state ? 



8. Do these parasites render abortive the female 

 Hymenoptera, in the bodies of which they are reared ? 



9. Do the sexes appear simultaneously ? 



10. Do the perfect Strepsiptera take any nourish- 

 ment ? 



1 1 . Of what use are those acute organs, termed 

 mandibles and the two-jointed palpi? 



1-2. What genera of bees are attacked in this 

 country ? 



This order consists at present of only four genera, 

 but it is not at all improbable, that when the minute 

 insects of other countries have been carefully col- 

 lected, others equally interesting will be discovered ; 

 indeed, North America and the island of Mauritius 

 have already furnished species of the order. 



The genus Xenos is distinguished by having both 

 the branches of the antennae inarticulate. It com- 

 prises two species, one found in Europe infesting the 

 bod}'- of the Polistcs Gallica (one of the social wasps), 

 and the other Xenos Peckii above noticed. 



In the genus Stylops the outer branch of the an- 

 tennae is flattened and tri-articulate. This genus 

 comprises several British species, and appears con- 

 fined to the genus Andrenn. 



The genus Elcnchus has the antennae similarly 

 jointed, but very long and slender, and the eyes 

 scarcely pedunculaled. Type Stylops tenuicornis of 

 Kirby. Elenchus Templetonii Westro. was discovered 

 at the Mauritius by Mr. Templeton. 



The genus Halictophagus, so named from being 

 supposed to be parasitic upon the genus of bees 

 Ha/ictus, has the antennae internally furnished with 

 four branches. A single individual of H. Curtisii was 

 taken by Mr. Dale near Lulworth Cove.Dorsetshire, 

 by brushing long coarse grass and thistles into a net. 



STREPSILAS Turnstone. A very interesting 

 genus of shore birds, belonging to the longirostral 

 family of Cuvier's Echassiers. They have a habit 

 different from that of any other birds which are met 

 with on the shores, numerous and varied as the inha- 

 bitants and visitants of them are. In the arrangement 

 of Linnaeus they were classed along with various 

 other birds in the genus Tringa (see TRINGA) ; but 

 they have very properly been made a distinct genus 

 by more recent naturalists. 



The generic characters are : the bill of mean length, 

 in the form of a lengthened cone, bent at the point, 

 straight in the greater part of its length, but very 

 slightly turned up at the point ; very strong, with the 

 crest flattened, and the point truncated ; the nostrils 



lateral, pierced longitudinally near the base of the 

 bill, and half closed by a membrane ; the feet of mean 

 length, naked a little way above the tarsal joints, 

 with three toes to the front and one to the rear, the 

 front ones united at their bases by a very short mem- 

 brane, and the hind one articulated upon the tarsus 

 higher up than the others ; the wings pointed, the 

 first quill being the longest. 



The principal habit of these birds which distinguishes 

 them from all their neighbours on the beaches, is 

 that after which they are named, and which is a very 

 expressive one, for they literally turn over stones, 

 when the tide is back, for the sake of the small ani- 

 mals that lurk under them. But they are not con- 

 fined to the turning over of stones, but turn sea-sand, 

 and all other substances below which the small ani- 

 mals of the beach hide themselves, if their strength 

 is able to perform the task. They do not bore in the 

 sludge as is the case with the longer and more flexi- 

 ble-billed members of the family, neither does it 

 appear that they range the beaches to fish up little 

 animals that are at large upon the surface, as is done 

 by the Tringas and some of the others, with which 

 the turnstones were formerly associated in the same 

 genus. They " stick to their vocation," and although 

 their labour appears to be more severe than that of 

 many of their neighbours, they are specially adapted 

 for it, and so they perform it. They are one of the 

 most striking instances we have of the endless re- 

 sources which are displayed in the animal kingdom, 

 accomplished too by very simple means. There is 

 nothing strikingly remarkable in the bill of the turn- 

 stone. It is a slant bill, without being in the least 

 heavy or loaded ; it is strongly set on the rounded 

 outline of the head ; the point is very hard, and the 

 basal point a little flexible ; and it has a bend up- 

 wards, so slight that it is just barely perceptible. All 

 these little circumstances, which one who knew no- 

 thing of the habits of the bird, would be apt to pass 

 over as indicating little or nothing, appear, however, 

 to produce the very best form of a bill for turning over 

 the pebbles on the beach, and seizing whatever may 

 be disclosed by the operation. We say that this is 

 the best form of a bill for the labour for which it is 

 intended, and we may say so with the utmost con- 

 fidence, because it is the one which Nature has made 

 for the purpose, and it is unique, as there is only one 

 species of turnstone. We are therefore constrained 

 to admit that this must be the very best form of an 

 instrument for turning stones ; that is, the one that 

 can accomplish the work with the least exertion of 

 muscular energy ; and, therefore, if we could fully 

 understand the mechanism and the working of this 

 bill, we should have a solution of a problem of no 

 small practical utility in some of the mechanical 

 arts. 



As we have said, there is only one known species 

 of turnstone, and this one is scattered over the shores 

 of very many parts of the world, but not in great 

 numbers any where, and only on particular spots. 

 The dry shingle where the turnstones have their 

 nests, and also the oozy and sludgy places where the 

 pebbles are partially imbedded in the mud, are 

 avoided by the turnstone, a beach where the ground 

 equally has some consistency, but not such as to 

 remain very wet, with little stones scattered about, is 

 what this bird chooses ; and as it does not invade 

 the pasture of any other bird, so there is not any 

 that invades its pasture, even although other birds 



