NOTES AND QUERIRS. 
217 
of tlie ' saiul-launce ' may be eiubedded iu tlie sand and mud without even a storm 
to destiMV them. Sinidar accidents, 1 was told, happen to tlie shoals of cajielin ; 
so that tliere is nothinf;' to iirevcnt the accumulation here of beds equally rich in 
the remains of fishes with those other dejiosits of ichthyolites that have excited 
so nuich interest and wonder." 
Mastodon Remains in Canada. — Some fossil remfiins of a monster animal, 
supposed to be those of a mastodon, have lately been discovered in the county of 
Elgni, C.W. The St. Thomas Despatch describes them as follows : — " We were 
sliown on Tuesday last, by Mr. Freeboni Berdan, the gigantic tooth of a monster 
animal, which was found on the farm of Mr. Sanuiel Berdan, two miles west of 
Five Stakes, some time last week, while digging in a light sandy loam on the edge 
of a small marshy spot, about twenty inches below the surface. The tooth shown 
us was about seven or eight inches in length across the face, by four or five in width, 
and seemed to have been broken out of the jaw. The surface was perfectly smooth, 
and appeared to us as if it had been petrified or very heavily enamelled. It was of 
a mottled gi'ey colour at the upper part, mnning down to a dark brown at the 
base. The interior was similar to a white calcined bone. Mr. Berdan also found 
two enormous tusks, eight and a half feet from one end to the other, and curving 
back so that the two ends are nearly parallel to each other ; also two thigh-bones, 
three feet long, an under jaw-bone over three feet long, several ribs from three to 
four feet in length from point to point, and six teeth, weighing six pounds or more 
each. These bones, as near as can be ascertained, are supposed to belong to a 
mastodon, an extinct species of the elephant, and have probably remained undis- 
turbed where they were found for centuries Viefore the continent was discovered. 
Some parts of them were in a high state of presei-vation, while others would 
cnnnble to pieces by the slightest touch, and their places have been filled by a 
substitute." 
Geological Excursions. — During the past month a series of practical field- 
lessons on Geology have been given by Piofessor IMorris to the students attending 
the Geological Class at University College, London ; the chief attention in these 
excursions being directed to the method of describing sections of the strata, the 
tracing their boundaries, and mapping their extent ; to the mode of occun-ence of 
fossils in the different layers, whether entire or broken, as indicating the condition 
under which they were deposited, and the natural history and characters of the 
animals, as evidencing the medium {i.e. marine or freshwater) in which they 
lived and died. 
The environs of London present many localities for studies of this nature. 
One excursion included the Woolwich and Charlton pits, where the fluvio-marine 
series of the Lower Tertiaries are well exhibited ; and their infraposition to the 
marine bed of London clay was shown by a traverse made to Plumstead Common, 
where the supeiijosition of the lower beds of the London Clay is exposed. The 
mammalian deposits of the Wickham Valley were also visited. Another excursion 
included the examination of the freshwater and mammalian deposits of Crayford 
and Erith, which show how these fluviatile accumidations of brick-earth were 
deposited upon an eroded surface of the Lower Tertiaries (Thanet sands) and the 
chalk ; tlie rich mannnalian and molluscan fauna obtained from these pits being 
examined in the collection of Mr. F. Spurrell, of Bexley, who kindly ofiered eveiy 
facility for the inspection. A third excursion embraced the more interesting 
geological features of the Isle of Wight, as exhibited in the fine sections of the 
Tertiary strata at White Cliff', and Alum, and Colwell Bays, and in the interesting 
section of the Wealden and Cretaceous series as exposed in the traverse made 
along the south part of the island, from Sandown to Compton Bay. 
Dendritic Markings ; Movements of Pentacrinite Plates in Vinegar. 
— " Dear Sir, — If you, or some of your numerous correspondents in the ' Notes 
and Queries ' department of your most excellent Magazine, will have the kindness 
to answer the following questions, I shall feel much obliged. 
" 1. What is the cause of the Dendritic appearances on Chalk ? 
" I have some fossils from a quarry at Benereuagh (County Deny), which are 
beautifully marked, especially the Echini. This appearance is. not confined to the 
