FROG 



FIMHISI.OKF 



13 



wandering blood-cells or 'leucocytes' carry the 



imtiiiiient ti other parts i>f the body. A casting 

 (if tin- outer layer of skill takes place ; tin- gill- HP- 



finally loM ; *the horny jaws are thrown off; the 

 large frilled lips shrink up; the mouth lows its 

 rounded suctorial form ami becomes much wider; 

 the tongue, pre\ iously small, increases considerably 

 in si/e ; tin- i-\i--, which as yet have been beneath 

 the skin, become exposed ; the fore-limbs appear, 

 the left one Iteing pushe<l through the spont-like 

 op. iiiug of tin- luiincliial chamber, and the ti-lii 

 one forcing its way through the operciilar fold, in 

 which it leaves a ragged hole' (Milnes Marshall). 

 As these momentous changes progress, and as 

 the supply of food afforded by the tail begins to 

 be exhausted, the animal recovers its appetite, 

 but this time carnivorously, feeding on available 

 animal matter, or even on its fellows. At this 

 stage tadpoles will clean a skeleton beautifully, 

 and Buckland describes them as showing a great 

 avidity for animal food, crowding round a dead 

 kitten, and nibbling at the toes of little boys who 

 wade in pools where they abound. With the 

 change of diet the abdomen shrinks, stomach and 

 liver enlarge, the intestines become both narrower 

 and shorter. The tail shortens more and more till 

 it is completely absorbed ; the hind-limbs lengthen ; 

 and eventually the animal leaps ashore a tiny 

 frog. For a considerable time the tadpole appears 

 to be neither male nor female, but differences in 

 nutrition, c. decide the question of sex. In 

 ordinary circumstances there are about as many 

 males as there are females, but Jung has shown 

 that by increasing the quality of food from fish to 

 beef, from beef to frog flesh, he could increase the 

 percentage of females to about ninety. See EM- 

 i:Kv>M)(jY, ENVIRONMENT, REPRODUCTION, SEX; 

 while for details of life-history, Milnes Marshall's 

 book should be consulted. 



Distribution and Related Species. The common 

 Brown Frog ( R. temporaria) is widely distributed 

 in Europe and Asia ; ' it is the most northerly of 

 known species, ranging in Norway to beyond the 

 seventieth parallel of latitude. In the Alps it still 

 frequents the waters at an elevation of 8000 feet.' 

 It is of course abundant in most parts of Britain, 

 and is common enough in Ireland, where, however, 

 it is said to have been introduced in 1696. 



Of wider distribution is the Green or Edible Frog 

 (R. escu/enta), which also occurs in Britain, though 

 not believed to be indigenous. Its habitat extends 

 from Scandinavia to North Africa, from France to 

 Japan. Widely distributed in the United States 

 are two forms the Shad- or Leopard -frog (R. hale- 

 ri'iiit) and the Wood-frog (II. sylvatica) which 

 some regard as identical with our common species. 

 The common Bull-frog of North America (R. 

 catesbiana ) is often brought to European zoological 

 gardens, has an appetite big enough to engulph a 

 sparrow, and a croaking power proportionate to its 

 large size. Like the edible frog on the Continent, 

 it is not unfrequently cooked. A large Indian 

 species ( R. tigrina ), another relatively huge, toad- 

 like species (7?. adspersa) from tropical Africa, a 

 single species from West Australia (jR. piipua}, and 

 another solitary form (R. krejftii) from the Solomon 

 Islands deserve to be mentioned. The genus is 

 unrepresented in the southern parts of South 

 America and in New Zealand. 



Related Genera. The family of true frogs or 

 K inidjc includes about two hundred species, ranked 

 in eighteen genera. They have always teeth in the 

 upper jaw, and a certain technical peculiarity in the 

 breastbone. One of the most curious forms ( which 

 have always teeth in the upper jaw) is the arlioreal 

 genus Rhacophorus, the ' Hying frog' described by 

 Wallace, in which the webs between both fingers 

 and toes are much developed. The tips of the 



lingers are dilated, and serve for attachment to 

 smooth or vertical surface*. The arboreal habit in 

 a resource which brings with it several physiological 

 adaptations, which must not l- too much insisted 

 upon in classification, for, as Huxley olmerves, the 

 common In-own frog 'at a year old will climb up 

 the vertical side of a glass vessel, flattening out the 

 ends of its toes, and applying its belly against the 

 surface of the glass, like a tree-frog.' Frogs, like 

 other amphibians, are usually unrepresented in 

 oceanic islands, but, besides the species of liana 

 already mentioned as occurring in the Solomon 

 Islands, three forms of Cornufer, ranked among the 

 Ranidte, ought to be noted on account of their 

 habitat in the Fiji Islands. The Dendro bat ii In- 

 form a family of small tree-frogs nearly allied to 

 the Ranida>, but without teeth. From one species 

 ( D. tinctorius ) the savage trills of some parts of 

 South America are said to extract a deadly jKiison 

 for their arrows. Less nearly allied to the Ranidae 

 are the toothless toads ( Bufonidae ), the horned toad 

 (Ceratophrys), the true tree-frogs (Hylidte), the 

 ' mid wife- toad ' or obstetric frog (Alytes obstetri- 

 cans), the tongueless Surinam toad (Pipa ameri- 

 cana), which are separately discussed (see TOAD, 

 TREE-FROG, &c.). 



The use of frogs for food is regarded with un- 

 necessary prejudice in Britain, but is very common 

 on the continent of Europe. The species chiefly 

 used is the edible frog (It. esculenta), which greatly 

 abounds in ponds and slow streams in France, 

 southern Germany, and Italy. They are taken for 

 the market by nets and by a kind of rake, and are 

 sometimes specially fattened in preserves. The 

 hind-legs are most frequently cooked, but other 

 muscular parts may be utilised. They are usually 

 dressed with sauces, and in flavour and tenderness 

 are comparable to chicken. The African species 

 (R. ad-spersus) is said to be much used by the 

 native tribes, and the gigantic bull-frog figures as 

 a rarity in the transatlantic menu. The frog 

 furnishes a very convenient vertebrate type to 

 the comparative anatomist, embryologist, and 

 physiologist, and is in this connection much more 

 useful than on the dining-table. 



See AMPHIBIA, BULL-FROG, NEWT, TOAD, TREE-FROG ; 

 and for showers of frogs, SHOWERS. See also St George 

 Mivart, The Common Frog ( " Nature ' series, Lond. 

 1874 ) ; A. Milnes Marshall, The Frofi : an Introduction 

 to A natomy, Histology, and Embryology (3d ed. 1888); 

 Ecker and Wiedersheim, Anatomic des Frosches (3 parts. 

 1804, 1881, 1882 ; trans, by Haslam, 1889) ; for figures, 

 G. B. Howes, Atlas of fruetteal Kltmentary Biol&jy 

 (1885); Bell's British Xeptitea (1839); Leydig's Anttra 

 Batrachia d. Deutschen Fauna (Bonn, 1877) ; Hoffmann 

 in Bronn's Thiemich, VI. (1873-78); British Museum 

 Catalogue of Amphibia ; and Hatchett Jackson and 

 Rolleston, Forma of Animal Life (1888). 



Frog, FISHING. See ANGLER, 



FrOgbit (Hydrocharis morsus-rance), a small 

 aquatic plant of the order Hydrocharidacea?, allied 

 to the water-soldier (Stratiotes), but with floating 

 leaves. 



Frogged, a term used in regard to uniforms, 

 and appued to stripes or workings of braid or lace, 

 as ornaments, mostly on the breast of a coat. 



Frogmore, an English royal palace and mau- 

 soleum in the park of Windsor, Berkshire. The 

 palace, purchased by Queen Charlotte in 1800, 

 after 18(51 was one of the dwelling-houses of the 

 1'rince of Wales. The mausoleum, a Komanesque 

 edifice, cruciform in shape and surmounted by an 

 octagonal dome, is consecrated to the memory of 

 the Prince Consort, whose remains were transferred 

 to it on 18th December 1862. 



Frog-spit* or CUCKOO-SPIT. See FROTH-FLY. 



Frohsdorf, a village in Lower Austria, 30 

 miles S. of Vienna, on the river Leitha, and near 



