356 



of 



tions performed by the Acalcphce is much I vered with short hair, and very much re- 

 increased when we reflect upon the extremely I semble those of a bird : the hind feet have 



small quantity of solid matter which enters 

 into their composition. This fact admits of 

 easy illustration, both in the Beroes and in 

 the Medusae. On one occasion, we took a 

 dead Cydippe, and placing it on a piece of 

 glass, exposed it to the sun. As the moisture 

 evaporated, the different parts appeared as 

 if confusedly painted on the glass ; and when 

 it was become perfectly dry, a touch re- 

 moved the only vestiges of what had been so 

 lately a graceful and animated being. With 

 regard to the Medusa:, we may mention an 

 anecdote which we learned from an eminent 

 zoologist, now a professor in one of the En- 

 glish universities [Prof. E. Forbes, we be- 

 lieve]. He had, a few years ago, been de- 

 livering some zoological lectures in a seaport 

 town in Scotland, in the course of which he 

 had reverted to some of the most remarkable 

 points in the economy of the Acalepluc. 



three toes on each, the middle of which is 

 somewhat larger than the rest, and all are 



furnished with sharp and strong claws : there 

 is also a very small spur or back toe, with 



After the lecture, a farmer who had been its corresponding claw. On each side the 

 present came forward, and inquired if he nose are several long hairs or whiskers ; and j 

 had understood him correctly, as having | the cutting teetli are sharp and strong, re- 

 stated that the Medusae contained so little | sembling those of a rat. In its attitudes and 



manner of progression this animal much re- ' 



of solid material that they might be regarded 

 as little else than a mass of animated sea- 

 watcr ? On being answered in the affirma- 

 tive, he remarked, that it would have saved 

 him many a pound had he known that 

 ner, for he had been in the habit of em- 

 ng his men and horses in carting away 

 rge quantities of jelly-fish from the shore, 

 and using them as manure on his farm, and 

 he now believed they could have been of 

 little more real use than an equal weight of 

 sea-water. Assuming that so much as one 

 ton weight of Medusae recently thrown on 



ployir 



large i 



the beach had been carted away in one load, 

 it will be found that, according to the ex- 

 periments of Professor Owen, the entire 

 quantity of solid material would be only 

 abo " 



mbles a bird ; generally standing, like the 

 Kangaroo, on its hind feet, and leaping with 

 much celerity, and to a great distance. It i 

 principally uses the fore legs in feeding, i 

 putting to his mouth the ears of corn, and ' 

 various other vegetable substances on which i 

 it feeds. 



The Jerboas inhabit dry, hard, and clayey i 

 ground, in which they make their burrows. 

 These are of considerable length, and run 

 obliquely and winding ; at about half a yard 

 below the surface of the ground, they ter- 

 minate in large excavations or nests ; they 

 are usually provided but with one opening, 

 though the animals are provident enougli to 

 make another passage, to within a short dis- 



ut four pounds of avo_irdupois weight, an j tance from the surface, through which they 

 amount of solid material which, if com- i rapidly penetrate in case of necessity. They 



pressed, the farmer might, with ease, have 

 carried home in one of his coat pockets." 



JERBOA. 



of rodent q 



. (Dipus.) 

 uadrupeds i 



This singular genus 

 peds may be considered as 



an intermediate link between the Squirrel 

 and the Bat, but agreeing with the latter 

 rather than the former ; while the enormous 

 development of its hind legs and tail cause 



keep within their holes during the day, 

 sleeping rolled up, with their head between 

 their thighs : at sunset they come out, and 

 remain abroad till morning. From the ra- 

 pidity with which they take their leaps (of 

 six or seven feet at a time), it is nearly im- 

 possible to overtake them. In leaping, they 

 carry their tails stretched out ; but in stand- 

 ing or walking, they carry them in a curved 



it to bear considerable resemblance in form form, the lower curve touching the ground, 

 to the Kangaroo. One species is a native of i In their wild state these animals are very 



Egypt, Syria, &c. ; and was known to 

 the ancients under the name of Dipus, 

 (two-footed), which is still its scientific 

 appellation. The most common species is 

 the Dipas sagitta. It is of a pale yellowish 



fond of bulbous roots; but, when confined, 

 they will feed on raw meat. They are tamed 

 without much difficulty, but require to be 

 kept warm. 

 There are some other species of the Jerboa ; 



fawn colour on the upper parts, and white [ by far the largest of which is the CAPE JER- 

 beneath ; the length of the body is about ' BOA, a native of the mountainous country to 

 eight inches, and of the tail ten, being the north of the Cape of Good Hope. Its 

 terminated by a tuft of black hair, the tip length from the nose to the tail is fourteen 

 of which is white, but the rest short and inches, and the tail itself somewhat more. 

 rough. The head is short ; the ears thin, The head is broad, the muzzle sharp, and 

 broad, upright, and rounded i the eyes large, the upper jaw longer than the lower: the 

 round, and dark coloured; the fore legs about ears are large, the whiskers long and black, 

 an inch long, with five toes to each foot, the I and the tail is extremely full of hair. It is 

 inner toe very small, but furnished with a an animal of great strength and activity, 

 sharp, crooked claw, like the rest ; the hind and will spring to the distance of twenty or 

 legs are extremely long, thin, sparingly co- , thirty feet at once. When eating, it sits up- 



