204 PROCEEDINGS OF THE ACADEMY OF [1883. 



MANAYUNKIA SPECIOSA. 

 BY PROF. JOS. LETDY. 



At the time of the discovery of the pretty polyzoan, Urnatella 

 gracilis^ of which a description is now in course of publication in 

 the Journal of the Academy, I found an equally interesting little 

 annelide, of which I gave a brief notice in 1858, published in the 

 Proceedings for that year, page 90, under the name of Mana- 

 yiinkia speciosa. The two were found in companj' together, 

 attached to the same stones, in the Schuylkill River, at Fairmount, 

 Philadelphia. They seem fitting associates, for while Urnatella is 

 nearly related with the marine Pedivellina, Manayunkia is closel}' 

 related with the marine annelide Fahricia. Manayunkia has 

 proved to be less frequent than Urnatella^ nor have I found it 

 elsewhere than in the localit}^ named. Recentl}^, several specimens 

 were submitted to my examination by our fellow-member, Mr. 

 Edward Potts, who found them attached to a fragment of pine- 

 bark, in Egg Harbor River, New Jersey. Independent of the 

 interest of finding the worm in a new locality, the specimens have 

 enabled me to complete an investigation of the animal so far as to 

 prepare the following description, though I have to regret that 

 the material has been insufficient to allow me to clear up several 

 impoitant points. I have had the opportunity of comparing 

 Manayunkia with a species of Fahricia living on our coast, and 

 have found the two to be so nearly alike, that I am prepared to 

 hear it questioned whether the former should be regarded as 

 generically distinct from the latter. 



Manayunkia forms a tube of mud, which it occupies. The tube 

 is composed of the finest particles, aglutinated by a mucoid secre- 

 tion of the worm. It is C3'lindrieal, straight or bent, mostly even 

 or slightly uneven on the outside, and sometimes feebl}' annulated. 

 It is attached partly along its length to fixed objects, with the 

 greater part free, directed downward and pendant. Most speci- 

 mens observed were single, but several were found in which two 

 or three tubes were conjoined, and in one instance five tubes with 

 remains of others were given off, in a candelabra-like manner, 

 from a common stem, as represented in fig. 2, Plate IX. From 

 the open mouth of the tube, the worm protrudes its head and 

 spreads its crown of ciliated tentacles, in the same manner as in 



