Btrtumarj) of ftrn'mattfr Mature. 231 



anatomical structure of the worm, premised 

 I a short statement of what is known with re- 

 gard to its habits, and the localities in which 

 it occurs endemically, showing that it is 

 found only in certain portions of the torrid 

 and north temperate zones in Africa and 

 Asia. It is especially frequent on the coast 

 of Africa, and thence derives its name of 

 Guinea Worm. When perfect, its average 

 length is from four to six feet : the body is 

 cylindrical, and of uniform size, or nearly 

 so, throughput ; there is no anal or other 

 opening visible at the caudal extremity of 

 the worm, or in any part of its length. The 

 cavity of the worm is occupied by innume- 

 rable young. In some worms, or in some 

 parts of them, these occupy the whole space, 

 whilst in others a grumous matter predomi- 

 nates, and only a few young are here and 

 there imbedded in it. The young Filarias 

 differ considerably in their outward form 

 from the parent worm, being furnished with 

 a long tapering tail, which constitutes about 

 two-fifths of the length of the body. The 

 life of Filariu Medincnsis as a parasite ex- 

 tends over from twelve to eighteen months. 

 When arrived at maturity, it comes to the 

 surface, and is either brought away or comes 

 away piecemeal, thus affording an opportu- 

 nity for the dispersion of the vivacious young 

 with which its interior is crammed. From 

 these facts, the author suggested that Filaria 

 Jlcilincnuis, in its parasitic form, presented 

 an instance, among the nematoid Entozoa, 

 of an intermediate or transitory generation, 

 such as have been shown by several natu- 

 ralists to exist in most of the lower classes 

 of animals. 



FIELDFARE. (Turdus pilaris.) A bird 

 of the Thrush kind, ten inches in length, and 

 weighing about four ounces. The head is 

 ash-coloured, inclining to olive, and spotted 

 with black ; the back and greater coverts 

 of the wings are of a deep chestnut ; the 

 throat and breast yellow, regularly spotted 

 with black ; the belly and thighs yellowish- 

 white ; tail dark brown ; legs dusky brown 5 

 bill yellow. The Fieldfare is a migratory 

 bird, making its appearance in this country 

 about the beginning of October, in order to 

 avoid the rigorous winters of the north, 

 whence it sometimes comes in great flocks, 

 according to the severity of the season, and 

 leaves us about the latter end of February 

 or the beginning of March. It builds its 

 nest in the loftiest trees ; and feeds on hips, 

 haws, and other berries, with various kinds 

 of worms, &c. 



Mr. Knapp, speaking of the Fieldfare in 

 his " Journal of a Naturalist," says, " In this 

 county [Gloucestershire], the extensive low- 

 hinds of the river Severn in open weather are 

 visited by prodigious nocks of these birds ; 

 but as soon as snow falls or hard weather 

 comes on, they leave these marshy lands, 

 because their insect food is covered or become 

 scarce, visit the uplands to feed on the pro- 

 duce of the hedges, and we see them all day 

 long passing over our heads in large flights 

 on some distant progress, in the same 

 manner as our larks, at the commencement 

 of a snowy season, repair to the turnip fields 



of Somerset and Wiltshire. They remain 

 absent during the continuance of those 

 causes which incited their migration ; but, 

 as the frost breaks up, and even before the 

 thaw has actually commenced, we see a large 

 portion of these passengers returning to their 

 worm and insect food in the meadows, at- 

 tended probably by many that did not take 

 flight witli them though a great many re- 

 main in the upland pastures, feeding promis- 

 cuously as they can. In my^ younger days, a 

 keen, unwearied sportsman, it was always ob- 

 servable, that in hard weather these birds in- 

 creased prodigiously in number in the coun- 

 ties far distant from the meadow lands, 

 though we knew not the reason ; and we 

 usually against this time provided tempting 

 bushes of naws,preserved in a barn, to place in 

 frequented hedges, near our secret standings. 

 When the Fieldfare first arrives, its flesh 

 is dark, thin, and scurfy ; but, having fed a 

 little time in the hedges, its rump and side 

 veins are covered witli fat. This is, in part, 

 attributable to suppression of perspiration 

 by the cold, and partly to a nutritive fari- 

 naceous food ; its flesh at the time becoming 

 bluish and clean. The upland birds are in 

 this state, from perhaps the end of November 

 till the end of January, according as the 

 hedge fruit has held out ; and at this period 

 they are comparatively tame : afterwards, 

 though the flights may be large, they become 

 wild ; and the flesh, assuming its darkness, 

 manifests that their food has not been 

 farinaceous. The distant foreign migrations, 

 which have been stated to take place from 

 the meadows of the Severn, I believe to be 

 only these inland trips ; and that the sup- 

 posed migrators returned to those stations 

 fat and in good condition, owing to their 

 having fed during their absence on the nu- 

 tritious berry of the white thorn. * * * Per- 

 fectly gregarious as the Fieldfare is, yet we 

 observe every year, in some tall hedge-row, 

 or little quiet pasture, two or three of them 

 that have withdrawn from the main flocks, 

 and there associate with the blackbird and 

 the thrush. They do not appear to be 

 wounded birds, which from necessity have 

 sought concealment and quiet, but to have 

 retired from inclination ; and I have reason 

 to apprehend that these retreats are occa- 

 sionally made for the purpose of forming 

 nests, though they are afterwards abandoned 

 without iucubation. * * * These retiring 

 birds linger with us late in the season, after 

 all the main flights are departed, as if re- 

 luctant to leave us ; but towards the middle 

 or end of April the stragglers unite, form a 

 small company, and take their flight." 



FILE-FISH. (Balittes^ There are se- 

 veral species which come under this general 

 denomination ; as the Unicorn File-flsh, the 

 European File-fish, and many others. The 

 first-named, the U.NICORN FILE-FISH (Ba- 

 listes monoceros), grows to a considerable 

 size, often exceeding two feet in length : the 

 body is of an oval shape, and, like most 

 others of this genus, it possesses the power 

 of inflating at pleasure the sides of the ab- 

 domen, by means of a pair of bony processes 

 within that part : the skin is everywhere 



x 2 



