HOLASCELLA ANCORATA. 41 



spilled, and with thin only slightly spined, distal rays occur among both. The 

 distal rays of the hypodermals appear to attain a greater length than the distal 

 rays of the hypogastrals, the former being usually over, the latter under, 400 ^ 

 long. 



The few root-tuft anchors observed are monactines. Their axial cross lies 

 in their terminal anchor-tyle. The shaft is covered with very irregularly dis- 

 tributed, backwardly directed spines 17 ii thick just above the terminal anchor- 

 tyle. The terminal anchor-tyle is similar to that of Holascella taraxacum. It 

 is, with the spines, 57-65 m broad and 74-90 m long. Its spines, the anchor- 

 teeth, are very irregular. 



The microoxyhexactines (Plate 23, fig. 8) measure 112-195 m in total chame- 

 ter. Their rays are regularly arranged, in the same spicule fairly equal, straight, 

 conic, pointed, 55-105 /x long and 3-5 m thick at the base. Their length is not 

 in proportion to their basal thickness, the shorter rays of smaller microoxyhex- 

 actines being often thicker than the longer rays of larger ones. The rays are 

 rather sparsely spined. The spines are sharp, not over 1 yu long, and directed 

 obliquely backwards. 



The onychomicroscleres (Plate 23, figs. 10b, 11, 14b, 15, 16) measure 65-90 fi 

 in total diameter, and have one to three end-rays. Many are microonychhex- 

 asters with only one end-ray on all the main-rays. Others are hemionychhex- 

 asters, with one end-ray on some, and two or, rarely, three end-rays on the other 

 main-rays. A few are true onychhexasters with two to three end-rays on each 

 main-ray. The main-rays are regularly arranged and, in the same spicule, 

 fairly equal. They are cyhndrical, smooth, about 5 m long and 1.5-2 ^ thick. 

 The end-rays are straight or only slightly curved, 28-50 ^ long, conic, at the 

 base about 1 m thick, and at the end 0.5-0.8 fi. They bear exceedingly minute 

 spines along their length, and at their end there are several, usually three or 

 four, large, more or less vertical spines. These terminal spines are not o\'er 

 7 M long, very slender, and curved, either simply, concave to the centre of the 

 spicule, or in an S-shaped manner. \Yhen two or three end-rays arise from a 

 main-ray, they enclose angles of 30° to 40° with its continuation; when there is 

 only one end-ray it Ues in the continuation of the main-ray, and usually passes 

 into it so gradually that main- and end-ray together appear as a simple, conic 

 hexactine ray. Sometimes a slight irregular thickening or change of direction 

 indicates the point where the main-ray passes into the end-ray. Such simple 

 rays are 33-35 m long. 



The discomicrosckres (Plate 23, figs. 5-7, 10a, 14a, 17-25) measure 130-220 /* 



