202 Herbert L. Haiukins — On Lanieria of Duncan. 



rapidly attained. The arrangement of the plates is similar in many 

 I'espects to that found in Conuliis. Of the three elements of a triad 

 the adapical one is a nai'row primary with parallel margins, the median 

 one is an extremely minute demiplate (hardly extending perradially 

 beyond the inner pore of its pair), and the adoral one is large, about 

 twice the height of the adapical one. The perradial suture is 

 zigzag for the length of about twenty plates from the apex, and then 

 becomes almost straight. The main series of tubercles is situated on 

 the large plates, near their adradial margins, and is persistent from 

 apex to peristome. The second series is on the narrow plates, almost 

 median, but becoming nearer to the perradial margin, and is persistent 

 through most of the area. Both series of tubercles are of about the 

 same size and are similar to those of the interambulacra. 



The interamhdacra are a little more than twice the width of the 

 ambulacra. They are composed of about twenty-seven plates per 

 column. The interradial suture is zigzag above, but becomes almost 

 straight at and below the ambitus. The main tubercle series is not 

 separable, in point of size, from the others. It is median on the 

 adapical plates, but keeps at an almost uniform distance from the 

 adradial suture throughout the column, thus appearing to pass down 

 the outside of the area. The subsidiary tubercles that are between 

 the two main series of an area are horizontally arranged, three or 

 four on each plate near the ambitus. Those towards the ambulacra 

 are in zigzag order — the principle of tuberculation being typically 

 that of the Discoidiidse. The surface between the tubercles is 

 gi'anulate. The test is somewhat worn adapically, but below the 

 tubercles are seen to be in deep scrobicules. 



E. 4571. A very large, crushed specimen. Diameter about 23, 

 height about 21 '5 mm. The ambulacra seem to have been slightly 

 projecting above the interambulacra. The madreporite is very 

 prominent. 



E. 4572. A small specimen with an obscurely pentagonal outline. 

 Diameter 13-6, height 11 "2 mm. The periproct is broken, and the 

 surface of the test weathered. The sutures are very clear, but surface 

 ornament is largely missing. Genital 4 seems to be without a pore, 

 but this is probably due to either abnormality or bad preservation. 

 The ambulacra are well shown adapically, and part of the anterior 

 area is diagram raatically shown in Fig. A. The sutures are 

 obscure below the ambitus. There are about twenty-five inter- 

 arabulacral plates per column. Ten plates adapically, and about five 

 adorally, are fairly high, but the middle region is composed of plates 

 of considerably less height. 



3. Description of Gcenholectypus cub.e, n.sp. 



The other three specimens that were associated with L. lanieri 

 (Nos. E. 4574, E. 11516, E. 11517) belong to a species of Coenholectypus. 

 The " individu subconique et a la face inferieure plane; hauteur 

 11mm., diametre 19 mm." of Cotteau (loc. cit., p. 11) undoubtedly 

 belonged to the same species. The variety Cotteau described (which 

 is probably founded on the specimen mentioned above) is certainly 

 a Cosnholectypus. The " face superieure legerement conique ", "face 



