292 Professor Bonney — Specimens from the Canadian Rockies. 



placed in my hands about half of a mound which had been knocked 

 off its edge, and a fragment of a rather thicker piece of quartzite, 

 slightly paler in coloui", on one side of which were two mounds and 

 part of a worm-burrow. I have had a slice cut from the former 

 parallel to the old vertical fracture, and another from the latter in 

 the same direction and practically through the middle of one of 

 the mounds going down about f inch into the quartzite. The two 

 are so similar that one description will suffice. They consist of 

 grains of quartz, a few being sharply angular, the majority sub- 

 angular, but a fair number rounded, which are sometimes slightly 

 enlarged by a secondary deposit of crystalline silica optically con- 

 tinuous. They exhibit in size and ordering a faint stratification. 

 I find also two or three small grains of a dull brown tourmaline, 

 two of them rather prismatic in outline and one included in a quartz 

 grain. Another slightly more abundant mineral occurs in grains, 

 rather oval in outline, as well as in not very definitely shaped 

 crystalline granules included in quartz grains ; these have a high 

 refractive index, are a dull madder-pink or brownish-purple in 

 colour, and are only faintly pleochroic. At first the polarization 

 tints seemed also dull, but a closer study showed that their natural 

 colour masked a real brightness, and the mineral was a dark zircon. 

 One or two grains of a rather granular dull yellow mineral with 

 crystalline outline resemble sphene more than epidote. Grains 

 or granules of an iron oxide, not seldom limonite, are also present, 

 possibly with two or three of a dark ferruginous rutile. All these 

 are scattered in a fairly abundant matrix, which is mainly composed 

 of a minute filmy mica-like mineral, colourless and with fairly high 

 polarization tints, probably a secondary product after felspar, traces 

 of which can here and there be detected. In the larger specimen we 

 find a green filmy or flaky mineral, doubly refracting, barely pleo- 

 chroic, with rather dull polarization tints, which is probably a variety 

 of chlorite ; in the other one there is less of this, but considerably 

 more of a minute, prismatic, fairly dark green mineral, probably 

 an epidote. Thus the microscopic structure, so far from being 

 favourable, is actually adverse to these mounds having a concretionary 

 origin. They cannot, I think, be regarded as casts of a Coelenterate 

 like a 'jelly-fish ' or any other perishable organism. Professor Collie 

 and myself came independently to the conclusion that they could only 

 be casts of pits made by an annelid, as it retreated from the surface. 

 I remember to have seen pits about this size between tide-marks on 

 a beach, some of which (I was told) were made by a Solen, others 

 by a lugworm. These casts, so far as size goes, might belong ta 

 PlanoUtes, with the burrows of which they are associated, but this 

 annelid generally moves horizontally, being thus distinguished from 

 Scolitlius, which descends verticall3^ Mr. Walcott, in his " Fauna 

 of the Olenellus Zone," ' gives a tube of ScoUtJius linearis leading to 

 the top of a piece of sandstone, where are the casts of three cup-like 

 depressions, and a " summit view of a group of casts of the cup-like 

 depressions " (the latter being sometimes more irregular in outline 



1 Teath Aun. Eep. U.S. Geol. Surv., p. 603 aud pi. Ixiii. 



