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Show 30 RIO DE JANEIRO. May-June, 1832·. existence of a division of the genus Planaria, which inhabits the dry land, interested me much. These animals ar~ of so simple a structure, that Cuvier has arranged them w1th the intestinal worms, though never found within the bodies of other animals. Numerous species inhabit both salt and fresh water; but those to which I allude were found beneath logs of rotten wood, even in the drier parts of the forest. In general form they resemble little slugs, but are very much narrower in proportion. I met with one specimen no less than five inches long. The lower surface, by which they crawl, is flat, the upper being convex: in this latter respect the terrestrial species all differ from the depressed forms of the aquatic. rrheir structure is very simple. Near the middle of the under surface, there are two small transverse slits, from the anterior one of which a funnel-shaped organ, or cup, can be protruded. This seems to act as the mouth. It is soft, highly irritable, and capable of various movements; when drawn within the body it is generally folded up like the bud of a plant. From the central position of the orifice, the animal has its mouth in the middle of what would commonly be called its stomach ! For some time after the rest of the animal has become dead from the effects of salt water, or other cause, this organ still retains its vitality. The body is soft and parenchymatous ; in the central part a transparent space, with lateral ramifications, appears to act as a system of circulation. Minute, black, eye-like specks are scattered round the margin of the crawling surface, and more abundantly close to the anterior extremity, which is constantly used as a feeler. In a marine species, I extracted from the central parts of the body vast numbers of little spherical eggs ; they were .006 of an inch in diameter, and contained a central opake mass or yolk. The terrestrial Planarire, of which I have found no less than eight species, occur from within the tropic to lat. 4 7 ° south, and are common to South America, New Zealand, Van Diemen's Land, and Mauritius. Some of the species May-June, 1832. TERRESTRIAL PLANARI..tE. 31 are longit~dinally striped with several bands of At first sight there is a remarkable false gay colours. these animals and snails, althou h a~alogy between from each other in all t' lg .so Widely separated I essen Ia pomts of . . suppose these Planarire £e e d on rotten wooodrg a£m zathw n. are always found crawlin on th ' or t ey decayed trees; and some :mall s e .under s~rface of old no other food, rapidly increased ~ecl~ens bemg kept with l d l' m size. Although 'l co oure Ittle animals th d' lik gai y-sitive to the light S; ey . IS e, and are very sen-v . me specimens which I b . an Diemen's Land I k t l' o tamed at H · ' ep a 1ve for nearly t avmg cut one of them trans l . wo months. parts, in the course of a fortn~;~:e { ~~toh t~o nearly equal perfect animals. I had h o . . a the shape of f h ' owever, so diVIded the b d h one o t e halves contained both th . £ . . o y, t at other, in consequence, none. In e ~n enor onfices, and the days from the operation th t e course of twenty-five have been distinguished 'fro~ more perfect h~lf could not other had increased much . . any other speCimen. The d m SIZe ; and towards · t · ~n ' a clear space was formed in the 1 s posteriOr m which a rudimenta h parenchymatous mass, distinguished . on th ry cudp-s aped organ could clearly be . ' e un er surface h spondmg slit was yet o en If h ; owever, no corre-weather, as we approach~d ~h t e mcreased heat of the all the individuals the be equator, had not destroyed would have com~let:; ~:n e no doubt that this last step known an ex . . 1 s ~tructure. Although so well-production or:~:;n::::n~:~ mteresting to watch the gradual mity of another animal It o~gan, out of the simple extreserV- e these Planarire . .im 1~ extremely difficult to preallows the ordinar i mfed1ately the cessation of life b d . y aws o change to a t th . o Ies become soft and fl 'd . h .. c ' mr entire U1 ' Wit a rap1dit h' h I h never seen equalled. A meth d .Y w 1C ave answered pretty ll o of preservatiOn that I found on a thin platew e f' wa.s to dry th e wh ol e am.m al rapidly t 0 miCa, for the bod th b ransparent, and allows th . y us ecomes I first visited the £ e t1~ternal structure to be seen. ores m which these Planarire were |