NO. 1706. C(ELENTERATES FROM LABRADOR, ETC.—BIGELOW. 305 



Gonads. — The most important character which distinguishes 

 Catahlema from the related genera Pandea, Tiara, and Clavula, '^ is 

 the form of the gonads. In C. vesicaria these organs have been well 

 figured both by A. Agassiz and by Maas, and the latter author has 

 pointed out the importance of the gonads in the classification of the 

 Tiaridse. The sexual organs, as in all Tiaridge, are purely interradial 

 (though in adults this position is largely masked by their growth); 

 and each gonad is primarily a horseshoe-shaped structure. The fea- 

 ture in which Catahlema difi^ers from related genera is that the inter- 

 radial portion of each gonad (connecting the two arms of the horse- 

 shoe) consists of a series of distinct vertical folds (pi. 30, fig. 3, go). 



Maas has considered an extreme development of lateral diverticulse 

 on the radial and circular canals as characteristic of Catahlema. In 

 this respect, however, the genus is so closely approached by Clavula 

 that it is impossible to draw any line between the two. In the larger 

 specimens in the present series the diverticulae on the radial canals 

 are well developed, some simple and some branched (pi. 31, fig. 6). 

 On the circular canal, however, they are much less prominent, form- 

 ing merely a jagged outline. This is a general condition no more com- 

 plex than I have described and figured for the Pacific Clavula fontata 

 (Bigelow, :09). 



Color. — After preservation with formalin, stomach, canals, and ten- 

 tacles are pale orange, and the gonads a deeper shade of the same color. 



Catahlema vesicaria is a purely boreal species. On the American 

 coast it has once been recorded from Massachusetts Bay, and never 

 from south of Cape Cod. It is common along the Labrador coast. 

 Haeckel (79) records it from Greenland, and Maas (:04) from the 

 Arctic Ocean near Bear Island. 



BOUGAINVILLEA SUPERCILIARIS (L. Agassiz). 



Plate 31, fig. 2. 



Hippocrene superciliaris L. Agassiz, '49, p. 273, pis. 1-3. 



Bougainvillea superciliaris L. Agassiz, '62, pp. 289, 344, pi. 27, figs. 1-7. 



Labrador, 30 miles southeast of Nain, surface; 5 specimens, p11 

 about 6.5 mm. high by 5 to 5.5 mm. in diameter. 



I can add little to the excellent accounts and figures of this species 

 which we owe to L. Agassiz ('49) and to Hartlaub ('97). 



The specimens, though larger than any observed by L. Agassiz, 

 are slightly smaller tlian the largest seen by Hartlaub, who records 

 individuals 8 mm. in height. Haeckel ('79) has recorded specimens 

 12 mm. in height, but Hartlaub questions whether these, in view of 



« For the medusan genus commonly known, since Lesson, as Turris, the name 

 Clavula, applied by Strethill Wright (Proc. Edinburgh Phys. Soc, vol. 2, 1859) 

 to the hydro id stage of Turris neglecta Lesson, must be used since the name " Turris" 

 is preoccupied by Bolton for a genus of mollusca. 

 Proc.N.M.vol.37— 09 20 



