450 H. F. Tomes — Inferior Oolite Ifadreporaria. 



of the septa with great distinctness. The so-called pseudo-synapti- 

 culse are very clearly shown, and appear as ledges passing con- 

 tinuously across the septa in lines parallel to the septal edge. There 

 is not the slightest indication of perforations between these ledges, 

 but there are well-defined dissepiments low down in the corallum. 

 The genus Thecoseris differs wholly from LeptophyUia in having im- 

 perforate septa and an investing wall with a well-developed epitheca, 

 giving to the calice a clearly- defined and prominent margin. These 

 differences sufficiently characterize Thecoseris, and at the same time 

 distinguish it from LeptophyUia. They also afford good reasons for 

 declining to accept the position of a subgenus assigned to them by 

 Prof. Duncan. 



When I stated my belief that Palvoseris would be found to be 

 identical with Thecoseris, I did not know that Zittel had already 

 referred it to that genus. That Thecoseris should be a Cretaceous 

 as well as a Jurassic and Tertiary genus, might be anticipated, and 

 accordingly a species has been described in Stoliczka's work on the 

 Cretaceous Corals of Southern India. 



Thamnastk^a expansa, sp. nov. 



I have met with a Thamnastrcea at Birdlip Hill, Gloucester, in a 

 Coral-bed which is an extension of the one at Crickley Hill, having 

 characters which do not accord with those of any species I am ac- 

 quainted with, and I therefore describe it under the above name. 



The corallum is broad and saucer-shaped, very thin, and has a 

 slight peduncle. The margin is extremely thin and wavy. The 

 epitheca is well developed and concentrically wrinkled. The calicular 

 surface is very slightly concave, and a little deeper in the centre. 

 The calices are extremely small, circular, and regularly distributed, 

 and there is very little disposition in the septal costse towards the 

 parallel arrangement observable in so many species of Thamnastrcea. 

 About twenty-four septa enter into and form the calice, twelve of 

 which unite in pairs at the fossula. The others are short. The 

 fossula is small, round, but not very deep. All the septa and septal 

 costge are very delicately papillated. 



Diameter of the corallum, 3 inches ; its thickness, \ inch. 



Distance from centre to centre of the calices, 1 line. 



THAMN ASTHMA HETEROMOKPHA, Sp. nOV. 



The corallum has a very complicated outline, somewhat resembling 

 that of Dimorphophyllia, but much more irregular and less compact. 

 Proceeding from a common centre, it expands upwards and outwards 

 into a considerable number of leaf-like and lobular parts, which are 

 in clusters, and have openings through and between them. The 

 calicular surfaces are horizontal and divided ; they are numerous, 

 and having their margin turned up, present extremely irregular 

 shallow cavities. All the under parts of these leaf-like lobes have 

 a well-developed and rngose epitheca. 



The calices are for the most part in rows corresponding with the 

 outer mai'gin of the lobes. They are shallow, but have a well- 

 defined and rather large fossula. There are from sixteen to eighteen 



