COCOONS OF ALLOLOBOPHOKA FCKTIDA. 



2O9 



our observation of copulating pairs, for in these cases also, the 

 longer part of the slime-tube lies anterior to the clitellum, 

 each worm finally withdrawing backward through the small end 

 of the cocoons. In the worm shown in Fig. I, the slime-tube 

 extends to the tenth segment, but it is not safe to assume 

 that in the living worm the tube may not extend still fur- 

 ther, possibly covering the spermathecal openings between the 

 ninth and tenth, and tenth and eleventh segments. The sudden 



Cocoon. Cftteltam. 



S/ime fu6e. 



FIG. 2. ; , 3. Forty-two anterior segments of a worm caught with a nearly mature 

 cocoon around its clitellum. Before being dropped into boiling water, the worm partly 

 withdrew from the cocoon, leaving it encircling the i6th-iSth segments. The cocoon 

 and segments are very much contracted, the cocoon appearing as a narrow, opaque 

 band around the worm. Such cocoons regain the typical oblong shape when removed 

 from the worm. The worm has partly withdrawn from the slime-tube, leaving the 

 anterior end projecting beyond its head. 



extension of the worm, when dropped into boiling water, possibly 

 causes such change in the position of the slime-tube, as shown 

 in Fig. i. 



On the other hand, we have no proof that the contractions of 

 the worm when captured do not result in an extension of the 

 tube beyond the point covered under normal conditions, and 

 that in the living worm the tube does not reach the spermathecal 

 segments. In living worms, we have seen the slime-tube, in 

 some cases, stop short of these segments, in others, completely 

 cover them, but it is impossible to affirm which condition pre- 

 vails when the worm is at rest. Fig. 3 shows a tube with its 

 posterior limit clearly indicated, by the impress of five seg- 

 ments posterior to the clitellum. A comparison with Fig. I 

 shows that the slime-tube in the captured worm stops short of 

 this point. 



Our method of securing cocoons in the process of formation 



