126 REPORT—1850. 
A List of Zoophytes found in the Vicinity of Peterhead, N.B., with a Notice 
of some new tothe British List. By C. W. Pracu. 
The author commenced by stating that when he went to Peterhead in December 
last, he took with him a paper of Mr. John McGillivray’s, containing a list of the 
zoophytes found on the coast of Aberdeen; this list he had verified, with the excep- 
tion of two, and he has added above as many more (including rare flexible kinds) ; 
the principal additions being calcareous, mostly Lepralias. He observed that many 
which are most abundant on the coast of Aberdeen, are either very rare or altogether 
wanting on the Cornish coast, and vice versd. The list now contained 107 species, 
all of which he had carefully examined before admitting them to the list. The first 
new one which he mentioned is a Cellularia of great beauty, differing from all figured 
in Dr. Johnston’s edition of the British Zoophytes, in the shape and arrangement 
of the cells having one tooth on the upper edge of each cell. The next is an detinia, 
which, from its colour and markings, very much resembles a Carnation. He concluded 
by saying, that although hitherto the shores of Peterhead had been considered to be 
bleak and wild, and barren of specimens of Natural History, it is quite a California 
in naturalists’ gold. 
On a peculiar Structure in the Submedial Pair of Rectrices of Vidua 
paradisea. By H. E. Srricxianp, F.G.S. 
When these feathers are in a young state, the barbs of both webs are united at 
their extremities to an intermediate filament, which becomes detached as the growth 
of the feather advances, and ultimately falls off. This filament is furnished on both 
sides with alternate tufts of ‘ barbules,’’ and these barbules possess hooked “ bar- 
bicels,”’ similar to those which exist on the distal side of the ordinary feather-barbs. 
By means of these hooks the filament embraces and clasps the barbs which are at- 
tached to its two opposite sides. This structure appears to be peculiar to the Vidua 
paradisea, and to the submedial rectrices only in that bird. Its object is probably 
the protection of the feather-barbs during the course of their development. But it 
is difficult to account for so complex a structure occurring in two feathers only, in a 
single species (so far as known) of bird. This singular structure was originally 
described and figured by the accurate Brisson (Orn. vol. ili. p. 123. pl. viii. f. 1.), 
but seems to have been wholly overlooked by later observers. Illustrative figures 
are given in Sir W. Jardine’s ‘ Contributions to Ornithology,’ 1850. 
On the Dentition of the British Pulmoniferous Mollusca. 
By ΝΥ. Tuomson, King’s College, London. 
In this paper the author gave a detailed account of the number, form and arrange- 
ment of the lingual teeth of this order, his observations being founded upon an 
examination of more than fifty British species, both land and freshwater. His object 
was to show, that all the different teeth on a tongue are only modifications of one 
typical form, which is to be met with in the central longitudinal row of teeth. Also, 
that the direction of the transverse rows, that is, the mode of divergence of the teeth 
from the central line on either side to the margin of the tongue, is regulated by the 
nature and extent of these modifications. The result of his researches throws much 
new light upon the structure and affinities of this order of mollusca; and amongst other 
points of interest, it tends to establish, as truly generic, the groups known by the 
names of Zonites and Zua. ‘The author places Zonites near Vitrina, and between Limax 
and Helix; he considers Zua as intermediate between Helix and Limneus, and Pupa 
(which scarcely differs from Vertigo) as the connecting link between Helix and Zua. 
On the Application of Photography to the Compound Microscope. 
By Wyviter T. C. Tuomson, Sec. R.P.S. 
The author stated that he had found it possible, by placing a sensitive plate, by 
means of a slide so constructed as entirely to defend it from the light, in the position 
of the second glass of the eye-piece of a compound microscope, to obtain with a low 
power a correct and delicate photographic picture of the microscopic field. 
