562 Prodromus of the 



which is at least three or four times as many as in the next 

 two species, closely set together, reminding one of the 

 pavement teeth of certain fishes ; the youngest saccules 

 always on the border next the partitions, from which side 

 they gradually increase in size until they attain their max- 

 imum at the opposite edge ; the distal end of each band 

 nearly touches the end of the arm which it enters, but the 

 proximal end terminates a short distance exterior to the 

 proximal end of the partition ; the digitiform bodies linear 

 lanceolate, extend iii three or four rows across the proximal 

 end of the partitions, and a very short distance along the 

 older border of each band : pedicel muscles transversely 

 triangular, deeply and profusely furrowed longitudinally ; 

 on the proximal side three of the furrows are so deep as 

 to divide the muscle into four great folds, which unite at 

 the distal side, corresponding to the apex of the triangle ; 

 each cord arises from the pedicel base, where it stretches 

 out to the centre, and gradually lessens in size as it ap- 

 proaches the disc ; at the basal two thirds of the pedicel 

 it is very near the outer surface of the gelatiniform layer, 

 but in the remaining third it gradually approximates the 

 axis of the pedicel, until, just within the entrance to the 

 main cavity, it reaches the inner surface of the same layer, 

 and then, in this relation, passing along a short distance, it 

 enters the oral side of the disc at the proximal end of the 

 corresponding partition ; the diameter of a cord about one 

 half the major diameter of a pedicel camera: the princi- 

 pal muscles of the disc are uniformly disposed layers, ex- 

 tending on each side of a partition to the margin of the 

 genital bands, along the margin of the genitals so strongly 

 developed as to appear like ligulate bands, as in H. octo- 

 radiata ; the fibrilla) diverge at very acute angles from each 

 side of the partitions, and, trending parallelwise with the 

 edge of the genital band, extend to the marginal muscle ; 

 the minor muscles uniformly diffuse, the fibrillae radiate 



