1874.] and Development of Peripatus capensis. 345 



They feed on rotten wood. They are nocturnal in their habits. They 

 coil themselves up spirally like lulus when injured. They have a remark- 

 able power of extension of the body, and when walking stretch to nearly 

 twice the length they have when at rest. They can move with consider- 

 able rapidity. They walk wfch the body entirely supported on their 

 feet. Their gait is not in the least like that of worms, but more like that 

 of caterpillars. When irritated they shoot out with great suddenness 

 from the oral papillae a peculiarly viscid tenacious fluid, which forms a 

 meshwork of fine threads, with viscid globules on them at intervals, the 

 whole resembling a spider's web with the dew upon it. The fluid is 

 ejected at any injuring body, and is probably used in defence against 

 enemies, such as insects, which would be held powerless for some time 

 if enveloped in its meshes. The fluid is not irritant when placed on 

 the tongue, but slightly bitter and astringent ; it is as sticky as bird- 

 lime : flies, when they light in it, are held fast at once. The fluid is 

 structureless, but presents an appearance of fine fibrillation when dry. 

 The animal is best obtained dead in an extended condition by drowning 

 it in water, which operation takes four or five hours. 



Only those points in anatomy are touched on which appear to have 

 hitherto been wrongly or imperfectly described. 



The intestinal tract is not straight, as described by Grube, but longer 

 than the body, and usually presents one vertical fold ; it presents 

 numerous irregular sinuous lateral folds, but is not enlarged in every 

 segment, as stated by Grube. Special regions, a muscular pharynx, short 

 O3sophagus, long stomach, and short rectum are distinguished in the 

 tract. The viscid fluid ejected from the oral papillae is secreted by a 

 pair of ramified tubular glands lying at the sides of the stomach and 

 stretching nearly the whole length of the body. These glands are those 

 described by G-rube as testes ; they show a common glandular structure, 

 but no trace of testicular matter. A pair of enlargements on the ducts 

 of the glands, provided with spirally arranged muscles, serve as ejacula- 

 tory reservoirs. The lateral elongate bodies lying outside the nerve- 

 cords, considered by Grube to be vessels, show a fatty structure, vary 

 much in extent, and are probably to be regarded as representing the fatty 

 bodies of Tracheata. 



No structure like that of the heart of Myriopods was found in the 

 dorsal vessel. 



The tracheal system consists of long fine tracheal tubes, which very 

 rarely branch : these arise, in densely packed bunches, from short com- 

 mon tubes, which open all over the body by small outlets in the epi- 

 dermis ; these outlets have no regular structure and are difficult to 

 see. The whole of the tracheal system, very conspicuous in the fresh 

 condition, becomes almost invisible when the animal examined has been 

 a short time in spirit, and the air has been thus removed from the 

 trachea. Hence the failure of Grube to see the in. The tracheae 



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