760 
ME. H. N. MOSELEY ON THE STEUCTTJEE AND 
suspended from objects lying in front of the animal, and having the appearance pre- 
sented by a bit of spider’s web with the dew upon it. When examined under the 
microscope the threads are seen to be fine and hyaline, with variously sized highly 
refractile spindle-shaped globules situate at intervals upon them (Plate LXXIII. fig. 4). 
They are thus very like the viscid threads of the spider’s web. The fluid of the 
globules is seen under a high power to contain a few fine granules. As it dries under 
the microscope, it forms into a tenacious mass, showing extremely fine lines pervading 
the threads in the direction of their length, and giving them a fibrillated appearance. 
The fluid is not perceptibly irritant when applied to the tongue, but has a slightly 
bitter and at the same time somewhat astringent taste. Small specimens of Peripatus 
soon exhaust their immediate supply of the fluid, and cannot be induced to make more 
than two or three discharges at one time even when squeezed hard ; but large speci- 
mens can make at least a dozen discharges one after another. The animals evidently 
use the fluid as a means of defence ; for when they are pricked with a needle or forceps 
about the side or middle of the body, they turn their head round and aim their dis- 
charge at the place at which the injury is being received. The tenacity of the threads 
formed by the fluid is so great and their viscidity so remarkable, that the meshwork of 
them thrown out over an insect or other such enemy would entangle it, and render it 
powerless for some time, even if it were of considerable size. The fluid adheres most 
tenaciously to the fingers, just like bird-lime ; .and when a large Peripatus, when first 
found and handled, shoots out its fluid over its own back and the fingers of the finder, 
it requires a very hard shake to free it from the hand. Whilst I am writing several 
flies have walked into some of the fluid which I caused a large Peripatus to discharge 
upon a glass slide in order that I might test the action of the fluid on my tongue. The 
flies are helplessly stuck fast ; and I believe that the fluid is quite sticky enough to hold 
small birds, though it dries too rapidly to be used for that purpose. The glands con- 
taining the fluid give some little difficulty in dissection of the animal, when this is 
conducted under water or in the dry condition, since they protrude out of the first 
incision, adhere tightly to forceps, scissors, or scalpel, and can hardly be disengaged 
without being torn, or very often without carrying away, together with themselves, the 
surrounding viscera, intestine, generative ducts, &c. 
Peripatus coils itself up, often, like lulus , in a spiral with the head in the centre of 
the coil ; and small specimens always assume this posture when they are severely pricked 
or maltreated. When in motion the animal extends its tentacles and body to their 
full length, thus becoming of nearly twice the length which it measures when at rest 
and proportionately narrower. The tentacles are kept in motion in search of obstacles, 
and the feet are moved rapidly in pairs, the alternate pairs moving together with consi- 
derable regularity, but at the same time with the peculiar progressive movement of a 
caterpillar. The gait is, in fact, extremely like that of a caterpillar. There is never 
any wriggling or sinuous movement of the body like that in worms. The ventral 
surface of the body is entirely supported free of the ground by the feet. The animals 
