— 
SECTIONAL TRANSACTIONS.—D. 323 
as to obscure the picture. Nevertheless, even in this group, life-history may be used 
in determining the immediate relatives of a genus, and, therefore, its family relation- 
ships. In some cases a habit was found to be a more constant feature than either the 
larval characters which are altered by yolk size and developmental rate, or the adult 
characters which may change without altering the mode of life-history. 
19. Mr. C. Tare Recan, F.R.S.—Oceanie Angler-Fishes. 
The Ceratioids, or Oceanic Angler-Fishes, inhabit the middle depths of the ocean, 
probably from about 500 to 1,500 metres below the surface; the females are slow-swim- 
ming fishes, uniformly blackish in colour, that attract their prey by a luminous lure. 
The males are dwarfed and parasitic on the females. Not quite fifty species are 
known. half of these having been described from the ‘ Dana’ collection, but the 
group is extraordinarily diversified, there being ten well-marked families. Some of 
the more specialised genera show remarkable modifications of structure of the lure, 
the mouth and the teeth. 
AFTERNOON. 
Excursion to the Hayling Island Mosquito Control Laboratory by 
Charabane. The Laboratory was officially opened by Sir Ronatp Ross 
during the visit. 
' Tuesday, September 1: 
Mornine. 
20. Joint Discussion with Section C (see page 316) on Distri- 
bution of Animals in relation to Continental Movements. 
21. Joint Meeting with Section C. 
Mr. M. A. C. Hinron.—The Pleistocene Mammalia of the British 
Isles and their bearing upon the date of the Glacial Period. 
Moderate opinion holds that there were two distinct glaciations of Britain, an 
earlier or ‘ major glaciation’ between the deposition of the Cromerian beds and the 
formation of the High Terrace of the Thames, and a later or ‘ minor glaciation’ 
towards the end of the Pleistocene period. An argument is now presented to show 
that the * major glaciation ’ of Britain was an episode of late Pleistocene time. 
The Cromerian beds and the terrace deposits of the Thames form parts of one 
great series, and afford no valid physical evidence of an early Pleistocene ‘ major 
glaciation.’ The fossil mammalia are definitely opposed to any theory which involves 
a break in the continuity of the terrestrial life of this country between Cromerian and 
late Pleistocene times. An older mammalian fauna of southern character, possibly 
of African origin, lingered from Cromerian to early Middle Terrace times; and: 
some of its species show definite evolutionary changes when traced from older to newer 
horizons. In later Middle Terrace times this older fauna was completely replaced by 
mammals of northern character or Asiatic origin, and these newcomers held the 
country until the close of the Pleistocene period when the most characteristic species 
became either totally or locally extinct. 
The argument as to a former cold climate commonly based upon the occurrence 
of such animals as the Varying Hare, the Snow Vole, and the Arctic Lemming is 
misconceived and unsound. 
AFTERNOON. 
Excursion to the New Forest. 
Exhibits in the rooms of the Section during the meeting included :— 
The Effects upon Plant-tissue of Salivary Secretion of certain Bugs, 
by Mr. Kennetx Smiru. 
Manz Cats’ Tails, by Miss Ruru C. Bamper (Mrs. BisBEE) and 
Miss E. CATHERINE HERDMAN. 
y¥2 
