ZooL— Vol. II.] ROBERTSON— ENTOPROCTA. 335 



says that the muscle fibers are distributed over the base of 

 the body. Other observers who say nothing of the distal 

 attachment of the muscle fibers represent them in their 

 drawings as extending a short distance into the calyx or 

 body, and as radiating around the base of the stomach. 

 Through the courtesy of Dr. W. S. Nickerson of the 

 University of Minnesota, I have had the privilege of exam- 

 ining some specimens of his new species, Loxosoma daven- 

 porti, a complete report of which has not yet been pub- 

 lished. I have prepared a few individuals in toto, stain- 

 ing and clearing them in oil, and the muscle fibers of the 

 stem come out distinctly. The indications are that part, at 

 least, attach themselves either to the floor of the atrium or 

 to the body-wall in the vicinity of the atrium. The opacity 

 of the organs of the body, however, prevents a clear view 

 of the distal attachment of the muscles of the stem, although 

 there is no doubt that they extend far into the body on the 

 ventral side. 



Seeliger (1889) gives an interesting stage in the develop- 

 ment of P. echinata from the larva, wherein the elements of 

 the stalk are directly continuous with those of the calyx; 

 and he says, " Auf diesem Stadium ahnelt die junge Pedi- 

 cellina einer Loxosoma, bei der ebenfalls die Sonderung in 

 Stiel und Kopfchen nur unvollkommen ausgepragt ist." 



Our species shows other Loxosoma affinities. In his very 

 interesting study of L. phascolosomahwi, Vogt (1876) con- 

 trasts Loxosoma and Pedicellina in the following words : 

 " Ce qui distingue, ontre les points mentionnes par M. 

 Nitsche, les Pedicellines et les Loxosomes en premier lieu, 

 c'est la position de I'appareil tentaculaire et la conforma- 

 tion generale du corps. L'appareil tentaculaire est place 

 sur la face ventrale chez les Loxosomes, tandis qu'il se 

 trouve au bout de I'axe de la tige et du corps chez les 

 Pedicellines; le corps des Pedicellines est comprime lat- 

 eralement, celui des Loxosomes verticalement. * * * 

 L'appareil tentaculaire est place exactementau sommetchez 

 les Pedicellines, sur le cote ventral un peu creuse chez les 

 Loxosomes. Ce qui, chez les premieres, se presente comme 



