FROM CHESAPEAKE BAY. 139 



my work there. I was anxious to obtain a more detailed knowledge of the structure of 

 the gonophores and to make out if there were any differences between the attached and 

 the free forms. To its interest scientifically it adds the attraction of beauty, for it is one 

 of the most graceful and beautiful hydroids I have ever seen. 



Lovenella gracilis, nov. sp. Plate 9, figs. 25 to 39. 



Trophosome. Hydrocaulus very slender, sparingly branched, with one or two annula- 

 tions at the base of each branch and hydrotheca, divided by transverse septa into numer- 

 ous short segments, three between each two hydrothecae ; branches simple and similarly 

 divided as the main stem ; hydrothecae arranged alternately on the stem and branches, 

 hyaline, rather stout, the length not more than twice the breadth, closed at the top by a 

 conical operculum usually consisting of eight pieces ; hydranths large and active with a 

 single verticil of ten or twelve tentacles and a large prominent proboscis. 



Gonosome. Gonangia developed from the bases of the hydrothecal peduncles, very long 

 and slender, largest at distal end and tapering toward the base, supported on short pedicils 

 consisting of one to three annulations; from three to five planoblasts developed in each 

 gonangium, aperture terminal. 



Planoblasts, twenty-four hours after liberation round and somewhat flattened in 

 outline, microscopic in size ; radial canals four, connected by a circumferential canal at the 

 periphery ; marginal tentacles six, of which two are very large, situated, at the peripheral 

 extremities of two opposite chymiferous tubes, the four smaller tentacles disposed one on 

 either side of each of the large ones ; at the points on the margin of the bell where 

 the other two chymiferous tubes join the peripheral canal there are rounded processes 

 which have the appearance of rudimentary tentacles, as yet undeveloped ; lithocysts four 

 in number and located midway between the points where each two adjoining chymiferous 

 tubes connect with the circumferential tube ; the tentacles and the entire surface of the 

 bell are well supplied with nematocysts. 



Until we have a more complete knowledge of the Lovenella clausa of Loven and Hincks, 

 it is a question of doubtful issue as to the relationships and systematic position of this 

 species. The genus Lovenella as characterized by Hincks is distinguished from its allies 

 by the possession of elongated, turbinate hydrothecae, crowned with a distinct conical 

 operculum composed of many convergent segments ; polypites with a large and prominent 

 proboscis. Reproduction unknown. The species L. clausa has a habit of growth very 

 similar to that of L. gracilis, the opercula of the hydrothecae are usually of eight segments 

 in both species, the tentacles are of about the same number and they both possess the 

 same style of large prominent proboscis. From these various points of similarity I con- 

 sider it better to put this new form in this genus rather than to create a new one for it. 

 When the reproduction of L. clausa has been made out we shall have an opportunity of 

 deciding the true relations of these two forms. 



The form of the hydrothecae are similar to those of Leptoscyphus and also those of 

 some species of Campanulina, but from the characters of both gonosome and trophosome, L. 

 gracilis can have no genetic relationships with either of these From a study of the growing 



