98 MR. E. E. WALKER ON THE GARNET-BEARING [Feb. 1904, 



material. They are typically developed north of Glaramara, and 

 are good andesitic ashes. They contain garnet-fragments, but 

 these are not common ; there can be no doubt about the clastic 

 nature of the garnets. 



The breccia found at Lining Crag (Greenup Gill) is a typical 

 rock (3754) consisting of lava-fragments with oval vesicles ; 

 fragments of a rhyolite with perlitic structure, the cracks 

 being filled with greenish chlorite. Garnet and felspar-fragments 

 occur. Perlitic rhyolites are occasionally met with in fragments 

 in many rocks. A good example (3926) occurs as an enclosed 

 mass in Dock-Tarn Gill. 



Above these greenish ashes and breccias comes a more com- 

 pact series of ashes, which may assume a more or less 

 pronounced ' streaky ' character. These are well seen on Allen 

 Crags, and south of the Angle-Tarn to Esk-Hause path : they 

 often contain perfect garnets. In a rock from Allen Crags (3871) 

 the ' streaky ' character is produced by lenticular patches of 

 chlorite squeezed out by pressure. Fragments of andesitic and 

 rhyolitic rocks occur abundantly, together with infiltrations of 

 chlorite. Felspar-fragments are also abundant. Garnets sur- 

 rounded by a felspar-ring are often found in these rocks ; ashes 

 from Esk Hause, near the path to Scawfell Pike, and on Scawfell 

 Pike itself, show this association well (3834 & 3845). A better 

 example is afforded bv the compact, blue, flinty ash above the 

 'streaky' rock in Whelpside Gill, Helvellvn (3839: PI. XIV, 

 %. 4). 



A very fine, exceedingly-compact, flinty ash, with oval concretions, 

 is found in the centre of the sync-line. Garnets are not often to be 

 seen in this rock, on account of its fineness: but a mass of ash and 

 breccia included in it on the Knotts of the Tongue (Esk Hause) 

 contained garnet-fragments. Minute garnets have been found by 

 Mr. W. M. Hutchings in the equivalent rocks of the slate-band in 

 the south, so that all the lower members of the Volcanic 

 Series, with the exception of the Eycott Group of 

 lavas and ashes, contain garnets. 



VIII. The ' Streaky ' Rocks of the Haweswater District. 



Garnetiferous rocks are well developed around Haweswater. 

 They present all the characteristic features of the ' streaky ' rocks 

 in the centre of the Lake District, but differ considerably in their 

 mode of distribution. I haver endeavoured on the 6-inch maps to 

 plot them out roughly, and to this end a peculiar nodular rock — as 

 pointed out on p. 18 of the Geological-Survey Memoir, on ' The 

 Geology of the Country between Appleby, Ullswater, & Hawes- 

 water' 1897 — forms a valuable guide. The rocks are developed in 

 bands, separated by lavas and ashes which do not contain garnets. 

 jSTow, the ' streaky ' rocks in the centre of the district, with perhaps 

 one exception, occur in one great group : the object of the mapping 

 was to determine whether this structure was original or produced 

 bv earth-movements. 



