360 
YORKSHIRE NATURALISTS’ EXHIBITION AT THE 
BRITISH ASSOCIATION. 
W. R. GRIST. 
The Yorkshire Naturalists’ Union is to be congratulated on the excellent 
exhibit given by its members at the Hull Meeting of the British Associa- 
tion. A brief reference was made in the last number of The Naturalist , 
but it has been thought that such a successful experiment merited a 
permanent record in the official journal. 
The main purpose of the exhibition was to present a bird’s-eye view 
•of some of the results of the organised scientific investigations of the 
various research sub-committees of the Union. Such a show is not a 
mere collection of ‘ specimens ’ arranged in a more or less haphazard 
fashion. In this case the exhibits were grouped under the various 
sectional activities, and were arranged to demonstrate the lines on 
which research work is being pursued. The following notes indicate 
the general arrangement and scope of the exhibition, and some idea of 
the appearance presented will be gathered from the illustrations showing 
two corners of the exhibition room. 
YORKSHIRE COMMITTEES OF RESEARCH & THEIR EXHIBITS. 
Section A (General Biology) : : — 
{a) Marine Biology Committee. — (i ) Exhibits of Living Marine 
Organisms from the Yorkshire Coast, by the Committee ; (2) Marine 
Tube-building Worms, Mr. Arnold Watson, Sheffield. 
(b) Micro-Biology Committee. — Diagrams based on Mr. R. W. 
Butcher’s examination of the Wharfe phytoplankton as illustrating that 
of one of the cleaner Yorkshire rivers. Monthly collections have been 
taken from this river at Harewood Bridge since January, 1921, along 
with data as to hardness, turbidity and water-level. The exhibit showed 
the relation of algal phases to habitat conditions. 
Section B (Vertebrate Zoology) :• — 
The Wild Birds and Eggs Protection Committee and The Yorkshire 
Mammals , Reptiles, Amphibia and Fishes Committee. — Exhibits : Photo- 
graphs of Yorkshire Birds — (1 ) Summer Visitors, arranged in sequence 
of arrival ; (2 ) Resident species, with photographs of favoured localities ; 
(3) Winter Visitors, in sequence of arrival, with notes and illustratioris 
as to favoured haunts ; (4 ) Birds of Special Habitats . 
(a) Mammals, Amphibians, Reptiles and Fishes Committee. — York- 
shire Mammals and Amphibians : Exhibits arranged on similar lines 
to those outlined above for birds ; Yorkshire Fisheries : The illustrations 
of fishes were grouped to show how the various species affect different 
portions of a river: — (1 ) Estuarine; (2) Slow reaches above tidal 
influence ; (3). Lower reaches with rapids and weirs ; (4) Rapid waters 
and upper stretches. 
Illustrations were provided by Messrs. Riley Fortune, Jasper 
Atkinson, E. W. Taylor, Ralph Chislett, W. Fowler, F. Vear and 
S, H. Smith. 
Section C (Conchology) : — 
Exhibit illustrating the variability and structure of the Mollusca of 
of the County,, by Mr. J . W. Taylor. Three frames of original drawings : 
(1 ) Varieties ol Helix aspersa, showing natural colours, together with 
ink drawings of internal organisation ; (2 ) and (3 ) Colour Variations in 
the British land shells ; (4) The distribution over the globe, indicating 
•approximately the relative dominancy of the different species as well 
as the chief evolutionary centre from which the most important forms 
arose. 
Naturalist 
