72 The American Naturalist. [January, 
lack in the power to climb clean, dry glass surfaces may, perhaps, be 
accounted for by the fact that these little fellows, dependent as they are 
upon respiration through a delicate cuticle, quickly succumb to dry- 
ness. I have watched individuals of both Pawropus and Europauro- 
pus as they ran up the sides of a vial or of a crystallizing dish, going 
easily where the surface was covered by fine particles of earth or hu- 
mrus, and falling off where the surface seemed clean.—F. C. KENYON. 
Lepidosiren articulata Not Distinct from L. paradoxa.?— 
Prof. E. Ray Lankester has lately made a study of the limbs of the 
various specimens of Lepidosiren conserved in the various European 
museums, and finds that in every case examined the skeleton of the limbs 
is hot a continuous cartilaginous rod, but is composed of a series of 
articulated cartilages. This removes the difference that Ehlers sup- 
posed to exist between his specimens from Paraguay and those from the 
Amazon basin, and caused him to create the species L. articulata. To 
further show that the specimens from the two river systems are in all 
probability of the same species L. paradoxa, Prof. Lankester compared 
the specimens in head-length units, with the following result, which 
shows differences of no specific importance. 
Brazilian, average: total length, 9.87; inter-membral, 5.25: post- 
membral, 3.5; cervico-dorsal, 3.21. 
Paraguayan, average: total length, 9.75; inter-membral, 5.21; 
post-membral, 3.59; cervico-dorsal, 3.2.—F. C. KENYON. 
The Regeneration of the Lens in the Eye of Triton.— 
Some two years ago we were astounded by the contents of a brief com- 
munication by Gustav Wolff in the Biologischen Centralblatte® bear- 
ing the title, “ Remarks on Darwinism, with an experimental contri- 
bution to the Physiology of Development.” In this the author brought 
forth the results of an experiment that flatly contradict one of the 
chief tenets of Weismann, inasmuch as he showed that the destruction 
of an organ formed from the ectodermic layer is followed by a regen- 
eration of the structure from a layer of cells of mesodermal origin. In 
other words, the lens of the eye of Triton teniatus, when destroyed, is 
reproduced by a lens that develops from the iris! Later on, Wolff 
published his final paper with illustrations. But the work was in 
great need of confirmation, This has been done by Erick Miiller, 
who seems to have begun his task with as much skepticism as might 
be expected. 
2 Trans. Zool. Soc., XIV., 11-24. 
? Bd., XIV (1894), No. 17. 
* Arch. f. Entwicklungsmechanik d. Organismen, I, 1895. 
5 Arch. f. mikr. Anat , xlvii (1896), 23-34. 
