360 



GREEFFIELLA 



set mi 



X1000 



character as the great bulk of the somatic setae. Among the somatic setae how- 

 ever are a few relatively large, hollow, open bristles of another character, resem- 

 bling the locomotor bristles found on Draconema, Desmoscolex, etc. For in- 

 stance, on the third and eighth 

 annule of the female, and on the 

 second and seventh annule of the 

 male, that is to say in the rows of 

 setae on these annules, there occur 

 subdorsal (on the second and third 

 annules) and dorsally submedian 

 (on the seventh and eighth annules) 

 pairs of spreading tubular open- 

 mouthed setae, or bristles, a little 

 longer than the regular somatic 

 setae. These special setae have 

 extra large bases and are probably 

 connected with glands. The rows 

 of ordinary cervical setae have a 

 fringe of shorter setae in their 

 midst. As before remarked, the 

 somatic setae are in fifty-six or 

 fifty-seven transverse rows, ex- 

 cluding those on the head, but 

 counting the finely pilose region 

 in front of the spinneret as two 

 annules. See Fig. 3. Passing back- 

 ward, the setae grow steadily longer 

 from the head to the tail ; the poste- 

 rior ones are about one and one-half 

 times as long as the spinneret, 

 while the anterior ones are some- 

 what shorter than the spinneret. 

 Back as far as the beginning of the 

 intestine, the rows of setae present 

 minute toothed fringes, accentu- 

 ating the annules. The conoid neck 

 ends in a rounded, somewhat 

 flattish hemispheroidal head, set off by a narrow, deep and distinct constric- 

 tion. The lips are amalgamated and fixed. Nothing is known concerning 

 the labial papillae. The pharynx is exceedingly minute and easily overlooked, 

 but is, in fact, a minute, simple, obscure, straight, regular, tubular, closed, 

 unarmed region about one-sixth as wide as the head and twice as long as wide ; 

 these measurements include its enclosing pharyngeal tissue. Under ordinary 

 circumstances there is to be seen here only a closed lumen. Passing back- 

 ward from the pharynx, the oesophagus for a distance two and one-half times 

 as great as the width of the head, is cylindroid; however, it widens slightly, 

 so that it becomes as wide as the head, or one-half as wide as the corresponding 

 portion of the neck, that is to say that portion of the neck marked by the fifth 

 circlet of cervical setae. At this point there is a rather faint diminution of 

 the oesophagus, which continues thence a little narrower, afterward widening 

 out, and then soon coming to contain granules like those found in the cells of 

 the intestine. This latter appears to begin about opposite the tenth row of 

 setae. There are two narrow ducts, one emptying into the posterior part of 



Fig. 1. Head end of Greeffiella dasyura. The 

 setae on several annules immediately behind the 

 head have been omitted so as to show internal 

 details more clearly, amph, amphid ; an, annule ; 

 int, location of the beginning of the intestine 

 (see also Fig. 2.) ; lum oe, lumen of the oesopha- 

 gus; oe, oesophagus; or, mouth opening; ph, 

 pharynx; set cph, cephalic setae, a number of 

 which are omitted ; set som maj, one of the larger 

 somatic setae; set som min, one of the smaller 

 somatic setae; set tb, tubular setae. 



