300 THE VOYAGE OF H.M.S. CHALLENGER, 



cases branch, lie apposed to cue auotlier, and anastomose freely. The narrow (from 

 2 to 4 mm. in diameter) tubular branches, which project externally, open outwards 

 by means of simple circular terminal openings. Here and there, but especially in the 

 neighbourhood of the upper extremity, there are also broad tubes, which are curved 

 outwards in a trumpet- or funnel-like fashion, and terminate with a wide irregularly 

 rounded margin. 



The entire system of these simple or branched and anastomosing tubes, which pass 

 out laterally from the central space, increases in thickness upwards, and is from 1 to 

 4 cm. broad. It forms a covering to the outer side of the cup, on the upper 

 terminal margin of which a certain outward curvature exhibits the structure of the 

 t ubework. If one looks through the large terminal opening into the lumen of the cup 

 — the gastral cavity — one sees the oval or circular inner openings of the tubes, which 

 increase in diameter upwards, and have a radial direction. 



In another specimen represented on PI. LXXX. fig. 2, the stalk and basal plate are 

 absent, and the axis of the cup is unbent. The greatly developed system of branched and 

 anastomosing lateral tubes increases in extent towards the top, but is much injured and 

 broken towards the thin margin of the cup, so that the latter are clearly marked in the 

 figure, and disclose the transverse beams of the often very obvious square-meshed 

 dictyonal framework. 



Close above the stalk the wall of the cup measures 2 "5 mm. in thickness, in the 

 middle of the body 1*5 mm., and on the upper margin only about 1 mm., i.e., the thickness 

 the wall in the individual wall-tubes. 



A third cup belonging to the same species was greatly weathered, and only its inferior 

 part was preserved. It exhibits, like the first mentioned, a slight bending of the axis, and 

 seems to have belonged to a very strong specimen, as it was borne upon a pedicel more 

 than 2 cm. in thickness. 



A plate-hke fragment with the well-preserved soft body, from 1 to 1'5 mm. in thick- 

 ness of the wall, exhibiting an irregular tubular form, and probably referable to the greatly 

 expanded upper lateral tubes of alarge cup, occurred among fragments of Farrea, Eurete, 

 and Aphrocallistes, in the materials collected by Dr. Doderlein in the Bay of Sagami, and 

 preserved in alcohol. I have figured this piece on PI. LXXXI. fig. 1, and hav« used it 

 especially in the study of the soft parts as well as of the more minute structural relations 

 of Periphragella. The beams enclosing the somewhat regular square meshes of the 

 dictyonal framework are either quite smooth, or beset more or less richly with small 

 simple spines. The free terminal bosses are always thickly spiuose. The nodes of inter- 

 section exhibit no marked thickenings. 



I have found uncinates only sparsely, and not always at right angles to the bounding 

 surface. They vary in length and thickness, and are surrounded by barbs. The 

 parenchyma includes a large number of scattered hexasters of two difierent types. Of less 



