306 Ernest W. Skeats: 



a form by the name of Dine sits ida, and referred it to the Cam- 

 brian series. 



7. The above paper is also referred to in Mon. Prog. Rep. 

 Geol. Surv. Victoria, No. 11, 1900, p. 26. 



8. Howitt, A. W . " Notes on Diabase and adjacent forma- 

 tions of the Heathoote Disitrict."' Special Rep. Dep. Mines, Vic- 

 toria, 1896 ; 16 pp., 3 pi. and maps [with appendix bv E. Lidgey, 

 p. 15]. 



Mr. Howitt described the more acid igneous rocks as plagio- 

 clase aplites and felspar porphyrites, a^nd the more basic rocks 

 as hornblende diorites, and varieties of diabasic rocks, including 

 diabase porphyrites, compact diabase, diabase schists, breccias 

 and extremely altered rocks. To some of these altered rocks he 

 applied the term spilite, and he noted that in the " regenerated 

 rocks '' the original structure of the rock has been more or less 

 completely lost, and replaced by calcite, quartz and epidote, and 

 in other cases the rock now consists entirely of actinolite. The 

 cherty rocks were regarded by Mr. Howitt as having been pro- 

 duced by the alteration of Low^er Silurian (Ordovician) shales by 

 the intrusion first of the diabase, and later of the gi'anitic rocks^ 

 The general characters of these chei-ty rocks reminded Mr. Howitt 

 of adinoles, although he pointed out that an analysis made of 

 one of the cherty rocks show^^ed a much higher silica and a much 

 lower soda percentage than is characteristic of the typical 

 adinoles. Mr. Howitt suggested by analogy with other areas in 

 Victoria, that the probable age of the intrusion of the igneous 

 rocks was the close of the Silurian or the earlier part of the 

 Devonian period. 



Mr. Lidgey, in an appendix to Mr. Howitt 's paper, withdrew ■ 

 his previous opinion that the diabasies^ wea-e lava flows inter- 

 bedded with the Ordovician series, and agrees with Mi*. Howitt 

 that they were intrusive, and have altered the Ordovician sedi- 

 ments for a distance of 2 to 15 chains from the diabase contact. 

 With Mr. Howitt's paper are included a general geological map 

 of the area on a scale of 2 miles to an inch, and four smaller 

 maps of parts of the area on the scale of 2 inches to a mile. 

 The names of the Geological surveyors ai-e not given, but I 

 gather that Mr. 0. A. L. Wliitelaw mapped the small area, in- 

 cluding the parish of Heathcote, and that Mr. Lidgey was 



