RODENTIA. 123 
We should place near the Dormice, the 
Ecutmys, Geoff—LoncueEres, Iilig. 
Four grinders also, but formed in a peculiar way; the upper ones con- 
sisting of two blades, bent into the shape of a V, and the under ones of 
one blade only that is bent, and of another that is simple. The fur of 
several species is very rough, and intermixed with flattened spines or 
prickles, like sword blades. From America. One of them, 
Ech. chrysuros; Hystrix chrysuros, Schreb. CLXX, B; Lerot a@ 
queue dorée, Buff. Supp. VII. 72. (The Golden-tailed Echimys). 
More than twice the size of the brown rat; it is a beautiful animal, 
of a chestnut-brown colour; white belly; an elongated crest of hairs, 
and a white longitudinal band on the head; the tail is long and black ; 
its posterior half is yellow. From Guiana. 
Ech. rufus; Rat épineux, Azzara, Voy. pl. xiii. (The Red Echi- 
mys). Size of arat, and of a reddish grey; tail shorter than the 
body. It is found in Guiana, Brazil, and Paraguay. It excavates 
long subterraneous galleries. 
Others, again, have merely the ordinary kind of hair, more or less 
rough. The most remarkable is the 
Ech. dactylicus, Geoff. (The Long-toed Echimys). Which is 
still larger than the golden-tailed one, and has the two middle toes 
of the fore feet double the length of the lateral ones. Its scaly tail 
is longer than the body; its fur is a yellowish grey, and the hairs on 
its nose form a crest directed in front.* 
Hyrvomys, Geoff. 
The Hydromys have many external points of relation to the Echimys, 
but they are distinguished from all other rats by their hind feet, two thirds 
of which are palmated; their twe molars have also a peculiar character in 
the crown, which is divided into obliquely quadrangular lobes, whose sum- 
mits are hollowed out like the bowl of a spoon. ‘They are aquatic. 
* Add the Echimys of Cayenne, the Silky Echimys. I suspect the Mus. para- 
doxus, Thomas, Lin. Trans. XI. (HeTEROmys, Lesson,) differs from the Echimys in 
its cheek-pouches only. However, not having seen its teeth, I cannot arrange it. 
a door admitted, between its lower edge and the floor, a current of air; and, in order 
to get rid of the inconvenience, the dormouse had previously fixed up a piece of 
board, which it absolutely detached from a shelf, and placed against the door. But 
this was not all. The dormouse, it was found, had untied a straw rope which encir- 
cled some bottles that lay in the cellar; of this it made a bed, which it lastly sur- 
rounded with a rampart curiously and ingeniously constructed; for this wall of se- 
curity was composed of the fragments of the bottles literally broken for the purpose 
of being placed as a wall of separation between the bed of the dormouse and the rats 
that might chance to invade it. The dormice are found in great numbers, in bur- 
rows, on the highest of the rocks of the Alpine mountains. They come out in wet 
weather, and generally announce the approach of rain by a shrill, and very peculiar 
whistle. The inhabitants of the Alps regard their appearance abroad as faithful 
indications of the weather. Dr. M. Hall, in the paper on hybernation already alluded 
to, states, that dormice, supplied with cotton wool, make themselves nests, and be- 
come lethargic.—Ene. Ep. 
