298 ORDER APONCHIA 



three, and behind the anus four, ventrally submedian papillae, the former sepa- 

 rated by spaces about one and one-half times as great as the width of the body. 

 Of those on the tail two are in front of the spinneret pore and two behind. Of the 

 two testes the anterior one is much the longer; both are narrow. The ejaculatory 

 duct is one-half as wide as the body, the vas deferens one-fifth to one-third. 

 The copulatory muscles occupy a space five times as long as the tail. The sperma- 

 tozoa are more or less ellipsoidal, and one-fifteenth to one-tenth as wide as the 

 body of the female. In the male, at a distance in front of the anus four to eight 

 times the length of the tail there are seven clavate, long glands connecting back- 

 ward with the ejaculatory duct. These glands darken in Flemming's solution. In 

 front of these glands, for a distance equal to four to five times the body-diameter, 

 there are about seventeen spherical glands not darkening in Flemming. These 

 also seem to connect with the ejaculatory duct. 



Habitat: Seaweed that drifted ashore after a storm at Ocean Beach, Miami, 

 Florida, U. S. A. Also found in beach sand at Ocean Beach. Flemming to 

 glycerine jelly. Fig. 78, p. 297. 



79. Aponchium cylindricolle n. sp. When the lips are closed the three onchia 

 almost completely fill the pharyngeal cavity. Extending backward and slightly 



outward from the bases of the teeth are refractive 

 i?^ ^L_ 2L_ >1 . 9 _. markings in the pharynx, indicating folds, 



evidence that the cavity containing the teeth can 

 1.8 6. 10. "''M 93.5 > 1 9 .. be everted. The pharyngeal cavity seems tc 



merge gradually into the lumen of the oesoph- 

 agus; it probably extends backward a distance equal to the diameter of the head. 

 Onchia of very slightly unequal size; the dorsal perhaps smallest, the submed- 

 ian ones equal. The oesophagus continues to have the same diameter until after 

 it passes through the nerve-ring, when it expands to form the elongated, pyri- 

 form, posterior bulb or swelling, three-fourths as wide as the base of the neck. 

 There is a distinct, somewhat cylindroid cardia, about one-third as long as the 

 neck is wide. The thick-walled intestine, which is separated from the oesophagus 

 by a broad and deep constriction, soon becomes three-fourths as wide as the body. 

 Its cross-section would display six to eight cells. The cells of the anterior por- 

 tion of the intestine for a distance twice as great as the corresponding body- 

 diameter appear to be of a slightly different character from those farther back, 

 as they almost invariably stain somewhat differently. The preliminary cells of 

 the intestine, namely, a transverse series of about six cells, are undoubtedly of 

 a larger size than those immediately following, and stain in a different manner; 

 they fail to take acid carmine stain, when the cells immediately following stain 

 well. These cells are packed with granules of rather uniform size. The succeed- 

 ing intestinal cells contain numerous yellowish granules of variable size, which 

 are rather irregularly disposed. A notable feature of the intestine is the lining, 

 which is unusually thick, and consists of two elements; an interior thin, refrac- 

 tive membrane surrounded by a non-staining layer nearly as thick as that portion 

 of the intestine containing the granules, already mentioned. In many parts of 

 the intestine this lining, composed of the two above-mentioned elements, occu- 

 pies fully half the optical longitudinal section. Anus raised, rectum somewhat 

 shorter than the anal body-diameter. The tail begins to taper slowly from some 

 little distance in front of the anus. Behind the anus it tapers somewhat more 

 rapidly, and is conoid to the terminus. The three saccate caudal glands form a 

 close tandem series in the anterior half of the tail. The nuclei of these cells 



