1190 Recent Literature. [ December, 
under similar circumstances. There can thus be no doubt about 
Sarsia possessing a visual sense. 
Dr. Romanes then describes his experiments on the covered- 
eyed Medusz to ascertain the amount of section which their 
neuro-muscular tissues will endure without suffering loss of their 
physiological continuity. In Aurela aurita (Fig. 1) the nervous 
system is compared to a disk of muslin, the fibers and mesh of 
which are finer than those of the finest and closest cobweb, and 
if we imagine the mesh of these fibers to start from these mar- 
ginal ganglia, we shall gain “a tolerably correct idea of the low- 
est nervous system in the animal kingdom.” Now if seven of 
these eight ganglia are cut out, and the disk mutilated as in Fig. 
2, yet the contraction waves, starting from the single ganglion 
Ni ANY vf ot 
ee So Joe 
a 
—= n y 
- Fic. 2.—Aurelia, with its disk cut radially. 
= left, “continued to zigzag round and round the entire series of 
_ sections,” 
n raction waves, emanating om /, passed’ in the direction rep- 
ted by the arrows without undergoing any appreciable loss 
completing the circular cut at z, the ring 
