558 Prodromns of the 



other genera ; the outer pistilliform tentacles smaller than 

 those in the next two or three inner rows, thickened and 

 humped on the exterior side, the proximal side as in the 

 others: genital bands elongate lanceolate, the proximal ends 

 of each pair almost touching each other across the axial 

 end of the intervening partition, from which point they 

 diverge and extend close up to the base of the tufts of ten- 

 tacles ; the base of the pedicel very broad ; the muscular 

 cylinder of the pedicel near the inner wall of the camera, 

 at about one sixth the distance between the latter and the 

 outer wall: principal muscles of the oral side of the disc 

 narrow ligulate ; one ligule accompanies each genital band, 

 running close along its border between it and the partition 

 from which it diverges ; marginal muscle ligulate, thick 

 in the middle, but thins out at both edges: gelatiniform 

 layer at the margin of the disc about as thick as the base 

 of a full grown tentacle, but it thins out to a mere film 

 about two thirds of the way to the centre of the body, and 

 then thickens again gradually toward the pedicel ; in the lat- 

 ter its thickness is about one fifth the diameter of the came- 

 ra ; in the pilasters it comprises the whole of their substance, 

 and is continuous with the inner division of the same sub- 

 stance in the main part of the pedicel, and in the thickest 

 part of the pilaster has a diameter a little less than one quar- 

 ter of that of the camera ; the fibroid bodies of the inner 

 division of the gelatiniform layer pass obliquely into the 

 pilasters to their periphery, crossing each other promiscu- 

 ously just within the paries of the same ; the digitiform 

 bodies extend a short distance along the tapering end of 

 each pilaster : lasso-cell pockets scattered over the oral 

 side. Size ; the disc 1" across, and 1" deep ; the pedicel ^" 

 long ; ^" diameter. Geographical distribution : Calvados, 

 France, Lamouroux, Milne Edwards, Keferstein ; Dover, 

 England, Aug. 1849, Owen ; Milford Haven, Wales, Sept. 

 1862, Stimpson in exped. collcgit. 



