Tke Austral Rhynchonellacea, 185- 



lines are developed on the costae as incipient tubular spines, some- 

 what developed to a market extent. The whole surface has a roughened 

 appearance from the numerous short but prominent spines. 



Dimensions. — Length, 9 mm.; width, 10 mm. Greatest thickness 

 of valves, 4 mm. 



Observations. — This Miocene form seems suggestive in its dis- 

 tinctly spinous characters, of a phylogenetic relationship with the 

 living T. doederleini. That Buckman's suggestion that " spinosity is 

 in itself not a generic character, it is only a stage of development 

 to which various stocks attain " may apply in this case, but in the 

 case of the squamosa type passing into nigricans, this principle does 

 not seem to apply, for squamosa and coelata have a spinous tendency, 

 but they afterwards develop into the less ornate type of nigricans in 

 which the growth-lines are sometimes scarcely perceptible. 



Occurrence. — Miocene. Table Cape, Tasmania. 



Tegulorhyxchta depressa, Thomson, sp. 

 Hemithyris depressa, Thomson, 1918, p. 117 (see also p. 108). 



Descripti07i. — (From Dr. Thomson's notes). T. depressa is a small 

 species with a short beak. It is broader than T. sublaevis^ and more 

 depressed, and possesses numerous fine ribs, and with imbrication to- 

 wards the margin. 



Dimensions. — Length, 14 mm.; breadth, 16 mm.; thickness, 8 mm. 



Occurrence. — (?) Oligocene and Miocene. Type locality, limestone 

 above tuffs, one mile north of Kakanui Quarry, Oamaru district. 



S. — Tegiilorhynchia TUBULiFERA, Tate, sp. (PI. I., fig. 8; pi. III., 



figs. 23, 24.). 



Rhynchonella (?) tuhuUfera. Tate, 1899, p. 257, pi. VIII., figs, 

 4, 4a. 



Description. — (Of the type). "Shell tenticular, suborbicular or 

 transversely quadrate-oval in margin outline; cardinal margin arched, 

 anterior and posterior margins rounded, front margin nearly straight. 

 Pedunculate valve depressed convex; beak bluntly and shortly pointed, 

 straight, and declinous from the hinge; foramen broadly triangular, 

 large, margined by two suberect, narrow lanceolate deltidial pieces." 



" The ornament of the valves consists of round radial costae, in- 

 creasing in numbers by repeated bifurcation, forty or more slightly 

 serrating the margin; there they are a little wider than the subconcave 

 furrows. The ribs are surmounted by stout truncated tabular spines, 

 sufficiently close together to be almost imbricated." 



''Dimensions. Length, 7.5 mm.; height, including beak, 6.7 mm.; 

 thickness of valves. 2.5 mm." 



Observations. — The type from which the above description was 

 taken was referred to by Tate as unique. There is, however, an im- 

 perfect specimen in the Dennant collection in the National Museum, 

 which is, without doubt, referable to the above species with which it 

 agrees in main characters and ornament, and differing in the slightly 



