2 Mr. R. Etheridge on Graptolites from 



from similar horizons. In addition to these Prof. M'Coy was 

 also able to recognize characteristic Bala and May -Hill 

 Sandstone (Upper Llandovery) fossils from several localities, 

 extending over a considerable area. Furthermore, from the 

 occurrence of the Trilobite Phacops longicaudatus , Murchi- 

 son, the presence of the Wenlock-shale series was surmised, 

 besides OrtJwceras bullatum, a well-known Ludlow form, from 

 beds on which a part of Melbourne itself stands. 



The few forms of Graptolites here noticed were collected, 

 some by my friend and former colleague, Mr. Norman Taylor, 

 others by the latter gentleman and myself; whilst a few have 

 since been received from Mr. G. H. F. Ulrich, through Mr. 

 R. Daintree, to both of whom I am much indebted for them. 

 The majority of the specimens are not in a good state of 

 preservation. 



Genus Tetragraptus, Salter. 



Tetragraptus bryonoides, Hall. PI. III. figs. 1-4*. 



GraptoUtlms bryonoides, Hall, Grapt. Quebec Group, p. 84, t. 4. figs. 1-11. 

 fDidymograptus caduceiis, Salter, Quart. Joum. Geol. Soc. 1855, ix. 



p. 87 ; ibid. 1863, xix. p. 137, fig. 13, a, b. 

 Didymograptus caduoeus, M'Coy, Exhibition Essay, 1861, p. 161. 

 Tetragraptus bryonoides, Nicholson, Quart. Joum. Geol. Soc. 1868, xxiv. 



p. 181. 



Frond consisting of four simple stipes, united in pairs at 

 their bases, and connected by a short funicle of variable 

 length, from the centre of which proceeds a short pointed 

 radicle, &c. (Hall). 



Of the Victorian forms of this species four figures are given. 

 Fig. 1, the impression of a frond showing the four stipes 

 flattened out, two broken off near the funicle, whilst on the 

 other two the cast of the solid axis is well defined. Fig. 2 is 

 a similar specimen, in which the whole of the four stipes are 

 displayed, but here, again, two more perfect than the others. 

 These two specimens have the stipes somewhat wider than 

 in the figures of this species given by Hall; they present 

 a certain resemblance to G. Bigsbyi, Hall, which I find 

 Prof. Nicholson considers hardly separable from D. caduceiis, 

 Salter, or T. bryonoides, Hall ('Annals,' 1870, v. p. 348). 

 Figs. 3 & 4 are the more common forms under wdiich this 

 species is found in Victorian rocks, and exactly coincide 

 with that described and figured by Salter as Didymogra<ptus 

 caduceiis. I have placed this above as a synonym of T. bryo- 



* In drawing these figures, one of the specimens was unfortunately 

 placed the wrong way up ; the stipes should be represented looking down- 

 wards. 



