OF KACHH AND KATTYWAE. 55 



curving above it, whilst one or two others are between it and the smaller tubercle, 

 according to the growth of the individual ; or the miliarias may be in a transverse line 

 above the larger tubercle, and one or more may be between it and the smaller. The 

 interradial plates halfway between the apex and peristome are about twice as broad as 

 they are high. According to the original describers, " they all show little fossettes in 

 their transverse sutures, which are rather deep, rounded, and rather elongate and sub- 

 angular in the vertical direction. The number and size of these fossettes often vary 

 according to position. Near the apical system two exist on each suture ; then three and 

 four (which are, however, very small) are seen with descent towards the ambitus. On 

 approaching the peristome the number and size diminish, and they become very small 

 and slightly pronounced." It is correct to state that, from apex to actinostome, there 

 are two vertical rows of fossettes in relation to each vertical row of plates ; also where 

 the angle of a plate impinges against the end of the suture of the one on the other 

 side of the median line there is a fossette ; and, moreover, occasionally where the suture 

 touches the poriferous zone there is one ; so that the number of fossettes varies with 

 growth and individuality. Now we find that they are all shallow, that a line of 

 suture crosses their floor, that when wearing has occurred the sutures are in plain 

 lines, and that there is no undermining or deep perforating as there is in Temno- 

 pleurus toreumaticus and in the species of Salmacis, 



The fossettes along the transverse sutures have their upper and lower margins 

 formed by oblique concavities in the upper and lower interradial plates ; and their inner 

 and outer boundaries are formed by processes which are in relation with the tubercles 

 of the plates. A large tubercle is on the middle of each plate, and nearer the actinal 

 surface a smaller tubercle is on either side of it at some little distance ; and the vertical 

 processes which limit the fossettes are abactinally and actinally to those three tubercles. 

 Very small tubercles or miliaries with a few larger miliaries form an arch over the' 

 large tubercle, and extend over the others, or are in a straight line. The fossette at 

 the angle of the plates in the median line does not reach to any depth. It is evident 

 that the plates are thick, and that, as they grow exogenously, spaces are left along 

 the line of the sutures. The fossettes are not seen in the very young form ; and in 

 some large specimens there is so little trace of them that they resemble species of 

 Salmacis, and the plates are then not bevelled. There is great variation in the 

 height of the plates. 



The peristome is small and sunken, and the cuts are exceedingly small. The 

 apical system is usually symmetrical, but in some specimens there is an obliquity of a 

 long axis which recalls Glyphocyphus. 



The apical system closely resembles that of Temnojyleurus toreumaticus. The 

 madreporic genital plate is the largest, and the others are large and project onto the 

 median interradial space with a bluntish angle ; the pore is large and not close to the 

 edge, although not far removed. The ocular plates are much smaller than the others, 

 and are concave towards the poriferous zones. A row of granules is on each plate 

 near its apical part. 



