ERRATUM 



To accompany the paper by R. A. Daly on "The Classification of 

 Igneous Intrusive Bodies," Journal of Geology, Vol. XIII, p. 485. 



Note. — Through oversight the "explanations" of the figures in the text were 

 omitted. 



EXPLANATIONS OF FIGURES 



Fig. 1. — Diagrammatic map of a composite dike in Arran. 

 (After Judd, Quarterly Journal of the Geological Society, London, Vol. XLIX (1893), P- 545-) 



1. Country rock (granite). 2. Augite andesite. 



3. Quartz-felsite. 4. Pitchstone-porphyry. 



The andesite was intruded along a fissure in the granite; then the felsite and porphyry were in 

 succession intruded along the middle plane of the andesite dike. 



Fig. 2. — Section of the Moyie Sill, British Columbia, at the crossing of the Movie 

 River and International Boundary. 



Illustrating a body which has the form and relations of a true sill, although the thickness is more than 

 2,500 feet. 



Fig. 3. — Section of a composite sill in the island of Skye. 



(After Harker, Tertiary Igneous Rocks of Skye, 1904, p. 204.) The stratified Lias was cut by the 

 sill of basalt; a later sill, of granophyre, was intruded along the middle plane of the basic sill. The latter 

 itself may have been double. 



Fig. 4. — Section of a composite laccolith. 



(After Harker, op. cit., p. 209.) The black is basalt, the white, granophyre. The laccolith cuts 

 heavily bedded lava flows. The maximum thickness of the laccolith is 150 feet. 



Fig. 5. — Section of an interformational laccolith. 



(After Weed and Pirsson, Journal of Geology, Vol. IV (1896), p. 412.) The floor of the porphyry 

 laccolith (in black) is composed of Pre-Cambrian crystalline schists; the cover, of Palaeozoic sediments. 

 The length of the section represented is about ten miles. 



Fig. 6. — Section of a typical volcanic neck. 



(After Geikie, Ancient Volcanoes of Great Britain, Vol. II. p. 273.) 



Fig. 7.— Diagrammatic map of a Tertiary "chonolith" of rhombenporphyry (crosses). 



Cutting intensely folded Palaeozoic sediments (broken lines) and Tertiary sandstones and conglom- 

 erates (white), occurring on the Kettle River, British Columbia. At its northern end the porphyry dis- 

 appears under a late Tertiary lava-cap (stippled). The Tertiary sediments are tilted and faulted. The 

 faulting was accompanied, or immediately followed, by the intrusion of the porphyry which field evidence 

 shows to have been injected as a body with a highly irregular form. 



Fig. 8. — Diagrammatic map and section of Ascutney Mountain, Vermont. 

 Illustrating a composite stock, composed of successive intrusions, in stock or boss form, of diorite, 

 syenite, and granite. A small boss of syenite (shown in black) cuts the diorite. These bodies cut crys- 

 talline schists, the attitude of which is indicated by the conventional symbol for strike and dip. 



Fig. 9. — Map of part of the West Kootenay District, British Columbia. 

 Illustrating a small batholith of syenite (vertical lining) and the southern edge of the great composite 

 batholith of the district. The latter is made up of the "Nelson granite" (thin, widely spaced, horizontal 

 lines), cut by the younger "Rossland Alkali granite" (more closely set horizontal lines) and by the 

 "Valhalla granite" (heavy horizontal lines). The maximum east-west width of the smaller batholith is 

 fifteen miles. 



