372 HYALONEMA (PHIALONEMA) PATERIFERUM. 



and 15.5-28 fi broad. The proportion of anchor-length to anchor-breadth is 100 

 to 76-100, on an average 100 : 92. Those of form D (Plate 52, figs. 27-29) are 

 35-77 M long, most frequently about 52 fi, and have anchors 11-27 m long, one 

 third to nearly a half of the whole spicule, and 9.5-22 /i broad. The proportion 

 of anchor-length to anchor-breadth is 100 to 62-91, on an average 100 : 76. 

 Those of form E (Plate 50, fig. 14; Plate 51, figs. 7-14) are 47-86, most 

 frequently about 73 n long, and have anchors 18-33 n, two fifths to nearly half 

 of the whole spicule, and 14-29 m broad. The proportion of anchor-length to 

 anchor-breadth is 100 to 57-87, on an average 100 : 72. Those of form F are 

 35-68 IX long, most frequently about 53 m, and have anchors 10-25 ix long, a 

 quarter to nearly half of the whole spicule, and 7-19 fi broad. The propor- 

 tion of anchor-length to anchor-breadth is 100 to 63-88, on an average 100 : 73. 



The small micramphidiscs (Plate 50, figs. 11-13; Plate 51, figs. 3-6; Plate 52, 

 figs. 24-26) have a straight shaft, 0.7-1.5 n thick, which is either cylindrical 

 and of uniform thickness throughout, or slightly and gradually thickened in or 

 near the middle. It usually bears a few scattered spines up to 1 /^ in length 

 in its middle-part. The terminal anchors are from under a third to two fifths 

 of the whole spicule in length. They are obtuse in shape and composed of about 

 eighteen teeth. The individual teeth arise vertically from the shaft, are nearly 

 straight in their basal part, and then curve downwards. This curvature decreases 

 distally. The ends of the teeth are nearly straight and enclose only small 

 angles with the shaft-axis, or are parallel to it. 



The small micramphidiscs are in forms A and B, according to Wilson (loc. 

 cit.), 20-25 fj. long. In form C they are 22-31 yu long, most frequently about 

 26 fi] in form D 18-31 n, most frequently about 24 n; in form E, 15-30 /i, most 

 frequently about 21 m; and in form F 14-24 yu, most frequently about 20 ix long. 

 Their anchors are in form C 4-1 ;u long and 5.5-12.5 ^ broad, the proportion of 

 anchor-length to anchor-breadth being 100 to 95-178, on an average 100 : 140; 

 in form D (Plate 52, figs. 24-26) 4-9 n long and 7-9.5 m broad, the proportion of 

 anchor-length to anchor-breadth being 100 to 100-200, on an average 100 : 153; 

 in form E (Plate 50, figs. 11-13; Plate 51, figs. 3-6) 4.5-9.5 ^ long and .5-10 /x 

 broad, the proportion of anchor-length to anchor-breadth being 100 to 87-150, on 

 an average 100 : 114; and in form F 3 6 ix long and 4-8 ^ broad, the proportion 

 of anchor-length to anchor-breadth being 100 to 100-175, on an average 100 : 140. 



Eight specimens and three fragments of this species were collected in the 

 central and eastern part of the Tropical Pacific. One specimen and three 

 fragments of form A were trawled ofT Panama at Station 3363, on 26 February, 



