576 ON THE EDIBLE FROG IN ENGLAND. [Dec. 2, 



The typical Rana esculenta is too well known to require description; 

 and it will suffice to refer the reader to Iib'sel's admirable illustrations, 

 and to the figure appended to this note, taken from a living specimen 

 from Foulden. The coloration varies immensely, and although the 

 green is the most frequent, I have also seen olive-brown specimens 

 (from Berlin) resembling very closely in colour the form lessons as 

 occurring in this country. For the latter it will be useful to give a 

 short description, which, with the coloured figures, will enable to 

 compare that form with other varieties of Rana esculenta. 



Snout obtuse, with very oblique loreal regions, its length slightly 

 exceeding the diameter of the orbit ; nostril equally distant from the 

 eye and the tip of the snout ; interorbital space half the width of 

 the upper eyelid ; tympanum three fourths the diameter of the eye. 

 Hind limb short ; when the limb is stretched forwards, the tibio- 

 tarsal articulation reaches the tympanum or not quite so far in the 

 female, the tympanum or a little beyond in the male. Inner meta- 

 tarsal tubercle very large and prominent, strongly compressed, semi- 

 lunar, closely resembling the spur of Pelobates ; its length equals 

 nearly two thirds that of the remaining part of the inner toe. Skin 

 smooth or feebly warty ; glandular lateral fold moderately promi- 

 nent, narrower than the upper eyelid. Olive-brown or bronzy 

 brown above, spotted with black, strongly marbled on the flanks, 

 where a light longitudinal zone remains unspotted ; glandular folds 

 lighter ; the sides of the head and the ground colour of the flanks 

 sometimes green ; canthal streak well marked, black ; upper lip 

 usually bordered with black ; tympanum chestnut-brown ; a pale 

 yellow or pale green vertebral line, frequently edged with black. 

 The dark cross bands on the limbs usually very irregular ; hinder 

 sides of thighs, axilla, and groin bright yellow or orange, marbled with 

 black. Lower surfaces more or less profusely spotted with blackish. 



Dimensions. ■$■ .,f. 



inillim. mulim. 



From snout to vent 64 78 



Length of head 22 29 



Width of head 22 28 



Diameter of the eye 6 8 



Interorbital space 2'5 3 



From the eye to the nostril 4 - 5 5 



From the eye to the tip of the snout 10 12 



Diameter of the tympanum 4 5*5 



Fore limb 34 42 



Hind limb 97 110 



Tibia 25 30 



Foot (from outer metatarsal tubercle) 34 39 



Inner toe (from inner metatarsal tubercle) . . 7"5 9 



Inner metatarsal tubercle 5 6 



EXPLANATION OF PLATE LV. 



Fig. 1. Rana esculenta, var. lessoncs, Camerano. From specimens from Stow 



Bedon. 

 Fig. 2. Rana esculenta, L. From a specimen from Fouklen. 



