— aa j— 
^ 
Rev. W. Houghton on two Species of Land-Planarim. 255 
have been evolved from it. The Sponges, it is on all sides 
admitted, are the simpler of the two. If simpler than the 
Sponges, its nature must have been Protozoic; and, knowing 
what we do of the highest representatives of the Protozoa, we 
may suggest the following :— 
l. The simplest Sponges have no skeleton. 
2. Sponges with skeletons are highly developed forms. 
3. All cup- or sac-shaped Sponges have skeletons. 
4. Prototype Sponges probably had no skeleton. 
V RUD Sponges, including Protascus, were not cup- 
aped. 
The word Protozoa may be substituted instead of Sponges 
in the foregoing lines. The reasoning is, as a matter of course, 
partly hypothetical, and is not laid down dogmatically ; yet it 
1s theoretical evidence in addition to the far graver one o facts 
opposed to the probability of Professor Hückel's hypothesis. 
r. Lankester has evidently not made himself familiar with 
the Paleozoic Zoantharia, or he would scarcely have contra- 
dicted so emphatically my suggestion that in that remote 
epoch the Corals had already reached the zenith of their de- 
velopment. Should he feel inclined to further cultivate their 
acquaintance, he may encounter forms far more complex than 
those peopling the existing seas. : 
ne sentence in Mr. Lankester's criticism of my paper is 
somewhat obscure, viz.: * We must also remember that the 
currents directed by cilia in the Sponges and the contractile 
organs round the mouth of Actinozoa are special developments 
gradually attained by these two diverging stocks which their 
common parent possessed but in general outline." The 
“homology,” “ homogeny,” or “ homoplasy " existing between 
XXV.—On two Species of Land-Planarie from Borneo. 
By the Rev. W. Houauton, M.A., F.L.S. 
To the Editors of the Annals and Magazine of Natural History. 
GENTLEMEN, : 
I have received the enclosed sketches of two species of 
Land-Planarie from Mr. Alfred Everett, Sarawak, Borneo, 
concerning which I shall be glad to receive what information 
any of your correspondents can give. Mr. Everett does not 
tell us any thing of the internal anatomy of these worms; but 
of their external form he thus writes :— 
o. Lis taken from a living specimen, and is pretty accu- 
rate; it was found on a leaf below Tambursan Cliff. The 
