412 



PK0F. P. AC. DUNCAN ON ECHINOIDEA 



1. CidaPvIs (Leiocidaeis) austeali-e, Dune. Quart. Journ. Geol. 



Soc. 1877. vol. xxxiii. p. 45, pi. iii. 



There is nothing to add to the former description of this species. 



2. There is another species of Leiocidaris in the fauna, but the spe- 

 cimen in the British Museum, Blanford Collection, from Bairnsdale 

 ( U E. 197"), is defective, there being only a portion of an inter- 

 radium and ambulacrum. But the structures enable this form to be 

 distinguished specifically from Leiocidaris australia?, nob. The am- 

 bulacrum is rather undulating and narrow ; the poriferous zone is 

 very slightly sunken; the pores are large ; the outer one of a pair is the 

 larger and elliptical ; the inner or adoral is round ; they are united by 

 a groove, and about seventeen pairs are in relation to a large inter- 

 radial coronal plate. Interporiferous area with a row of small, im- 

 perfect secondaries, with slightly raised scrobicules and a small boss, 

 no mamelon, placed close to the poriferous zone, and a series of 

 smaller secondaries nearer the median line, in a vertical row extend- 

 ing along the middle of the area, but not reaching much actinally or 

 far towards the apex. The primaries of the interradia are large ; 

 the scrobicules are distinct, nearly circular ; and there is a row of 

 small secondaries and a few granules between them and the hori- 

 zontal sutures of the plates. The boss is broad at the base and 

 conical, and the mamelon is contracted at the neck and is perforated. 

 There is no crenulation. The margin of the scrobicular circle is 

 sunken, and is surrounded by a row of small secondaries made up of 

 an elongated raised scrobicule, longest transversely, and a small boss ; 

 there are a few smaller tubercles placed beyond the circle, and 

 fitting in between the larger, so as to complete the circle, and a few 

 exist beyond it. Two or three rows of still smaller tubercles extend 

 along the plates beyond the circle towards the median line, and the 

 median area of the interradium is narrow. 



Numerous spines are in the collection, and the large and nearly 

 smooth ones may be associated with this genus. 



3. Goniocidaeis, sp. 



There are several spines of a species of this genus present in the 

 Cape Otway deposits. 



4. Saeenia tertiaeia, Tate, Quart. Journ. Geol. Soc. 1877, vol. xxxiii. 



p. 256. 



This interesting species has been examined by me (' Annals and 

 Magazine of Natural History,' 1878, ser. 5, vol. ii. p. 61), and recon- 

 sidered by A. Agassiz (Report on the ' Challenger " Echini, p. 51, 1881). 

 It is a most interesting form, and large and well-grown. 



The occasional entry of one of the radial plates into the formation 

 of the anal ring is not enough to remove the species from the genus, 

 for a similar entry is also inconstant in the recent Salenia ha$tigera t 

 A. Agass. Moreover, Cotteau, Peron, and Gauthier have described 

 Algerian Cretaceous Salemce, which have a radial plate entering the 

 anal ring ; and Salenia Blanfordi, Dune. & Sladen, from the Eocene of 



