Order lAicernarice. 549 



pedicel muscles very large, equally trihedral, with slightly 

 convex sides ; at the base of the pedicel they extend from 

 the axis to very near the surface, terminate truncately, 

 and each occupies about one eighth the whole area, the 

 camera, each respectively filling up the other four eighths ; 

 passing toward the urn the muscles gradually diminish their 

 radial diameter, and just before they enter the proximal ends 

 of the partition of the urn they narrow rapidly to a much 

 less diameter : principal muscles of the oral side of the urn 

 uniformly pennate, the fibrillse diverging symmetrically on 

 each side of the partitions; marginal muscle imbedded 

 in the distal side of the greatly thickened musculo-gelati- 

 niform layer, which forms the raised border ; the muscle is 

 very broad, its breadth equal to the length of the tentacular 

 anchors ; at its free margin it is very thick, and gradually 

 thins away to a sharp edge at the junction with the termi- 

 nation of the aboral side : gelatiniform layer of the aboral 

 side of the urn moderately thick, nearly uniform, being 

 slightly thinned toward the pedicel, but thickening again 

 farther along, and passing into the pedicel retaining about 

 the same incrassation exterior to the region occupied by 

 the camertE and muscles, until at the base it abruptly be- 

 comes thinner by two thirds ; at the axis of the pedicel it 

 is thickest where the cameras and muscles are thinnest, 

 and projects a short distance between the camerae, but 

 the contact of the sides of the latter and the muscles pre- 

 vents it from communication with its peripheral portion : 

 two irregular rows of large lasso-cell pockets extend from 

 the distal end of the genitals toward the margin of the 

 urn. Size " \ seldom § of an inch long ; of which the 

 cylindrical thin stem forms the one, and the beaker-form 

 body the other half." Geographical distribution : coast of 

 Norway, Sars; Orkney Is., Allman. 



of different genitals, and this my prolonp;ed investigations, for the past two years, 

 have induced me to consider as the peculiarity of the type of this family. 



