Hydra, 
Z. HYDROIDA. 
107 
off it may safely be ingrafted on the body of any other which may 
chance to want one. You may slit the animal up, and lay it out flat 
like a membrane, with impunity ; nay it may be turned inside out, 
so that the stomachal surface shall become the epidermous, and yet 
continue to live and enjoy itself. * And the creature even suffers 
very little by these apparently cruel operations, 
— “ scarce seems to feel, or know 
His wound, — ” 
for before the lapse of many minutes, the upper half of a cross sec- 
tion will expand its tentacula and catch prey as usual ; and the two 
portions of a longitudinal division will, after an hour or two, take 
food and retain it. “ A polype cut transversely, in three parts, re- 
quires four or five days in summer, and longer in cold weather, for 
the middle piece to produce a head and tail, and the tail part to get a 
body and head, which they both do in pretty much the same time. 
The head part always appears a perfect polype sooner than the rest.” 
u And what is still more extraordinary, polypes produced in this man- 
ner grow much larger, and are far more prolific, in the way of their 
natural increase, than those that were never cut. It is very common 
when a polype is divided transversely, to see a young one push out 
from one or other of the parts, and sometimes from both of them, in 
a very few hours after the operation bas been performed : and par- 
ticularly from the tail part, two or three are frequently protruded in 
different places, and at different times, long before that part acquires 
a new head, and consequently whilst it can take in no fresh nourish- 
ment to supply them with : and yet the young ones proceeding from 
it, under these disadvantages, thrive as fast, and seem as vigorous as 
those produced by perfect and uncut polypes.” t 
When such things were first announced — when to a little worm the 
attributes of angelic beings were assigned % — it is not wonderful that 
* Trembley had several by him “ that have remained turned in this manner ; 
their inside is become their outside, and their outside their inside : they eat, 
they grow, and they multiply, as if they had never been turned,” — Phil. Trans, 
Abridg. viii. 627 ; and his Mem. 253, &c. 
f Baker, lib. s. cit. 92, 93. 
$ “ Vital in every part, not as frail Man 
In entrails, heart or head, liver or veins, 
Cannot but by annihilating die ; 
Nor in their liquid texture mortal wound 
Receive, no more than can the fluid air, 
All heart they live, all head, all eye, all ear, 
— — — — and, as they please, 
They limb themselves, and colour shape or size 
Assume, as likes them best.” Milton, 
