84 Yorkshire Naturalists’ Union: Annual Report, 1912. 
in recording their observations to indicate more clearly than 
heretofore the conditions of the habitat of the dominant 
species and to take note of any factor likely to account for the 
distribution of the species. In Bryology there is a very 
promising field and we record with pleasure the efforts now being 
made to regard moss distribution from the ecological stand- 
point. Plant Associations receive due attention at the Yorkshire 
Naturalists’ Union’s excursions, and this is reflected in all the 
reports published during the year in The Naturalist. More 
detailed accounts than usual have been given, for which 
reference may be made to The Naturalist for the months of 
March, April, June, July, August, September and October. 
As an outcome of the excursions special areas are receiving 
attention, from which interesting results may be expected. 
BRYOLOGICAL COMMITTEE.—Mr. Wm. Ingham, B.A., 
writes :—Mr. C. A. Cheetham initiated the happy plan of organ- 
ising excursions to various places during the past year. The 
first was held at Knaresborough, on 27th January, and was 
very well aitended. The chief plants found on this occasion 
were Thuidium hystricosum, Barbula sinuosa, Weisia calcarea 
and the liverwort Haplozia pumila. It was interesting to see 
the typical greenhouse liverwort, Lunularia cruciata, well 
established by the river side. A full account of this Excursion 
will be found in The Naturalist for March, 1912. 
The next excursion was to Pateley Bridge on 16th March, 
when the following interesting mosses and hepatics were 
found :—Schistostega osmundacea with its interesting light- 
emitting lenses on its protonema, Ditrichum homomallum in . 
fruit, Tetraphis browmana, Nowellia curvifolia on earth- 
covered rocks, Bazzania trilobata, Lepidozia pinnata, and 
Jubula hutchinsiae. A prominent moss on rocks in the river 
was the very distinct variety vivulare of Eurhynchium myosur- 
oides, which to the present has a scanty distribution in the 
British Isles. Many members were present and the outing was 
very successful. An account of the excursion will be found in 
in the April Naturalist. 
The bryologists joined the excursion of the Union to 
Skipwith Common on 4th May, a report of which appears in 
The Naturalist for June, 1912. The chief bryological feature 
was the presence in considerable quantity of Campylopus 
- atrovirens var. muticus, which has hitherto been considered 
as quite a montane moss. 
At the Tanfield excursion on 15th June (see Naturalist, 
August, 1912), Mr. Barnes found the rare Thuidium hystricosum 
new to North West Yorkshire, also the very rare Hepatic 
Pedinophyllum interruptum. 
It is worthy of mention that in The Naturalist for July, 1912, 
is an account of a pre-glacial moss similar in habit and structure 
Naturalist, 
