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lateral teeth gradually pass from one form to the other ; and 
1 cannot conceive any reason why all the forms figured may 
not belong to the genera of one family.” 
On the Boring of Certain Annelids. By Dr. McIntosh. 
2 plates. Annals of Natural History, October, 1868. — Dr. 
McIntosh shows that a chemical explanation of the means 
of boring of Leucodore is untenable, since that Annelid bores 
in shale. He figures the bristles of the fifth segment, which 
differ from those observed by Mr. Bay Laukester in a 
species of boring Leucodore. It is probable that, in this 
case, “microscopic diagnosis” will prove the existence of 
two common species of this genus. 
Apparatus. — Camera Lucida. Scientific Opinion, No- 
vember, 1868. — A new camera-lucida to be employed in 
taking sketches of living creatures, such as infusoria, has 
been constructed by Mr. Charles Collins, optician. The 
design is by Dr. Colies, of Calcutta. In using the ordinary 
camera-lucida, or the tint-glass reflector, the body of the 
instrument must be placed horizontally, or nearly so. 
Hence, when unmounted preparations in liquid are laid 
upon the stage they move out of the field of view, or the 
liquid in which they are placed does so, and no adequate 
sketch can be made. This difficulty is obviated in the 
new camera by placing a right-angled tube containing a 
right-angled prism at its angle, between the body of the 
microscope and the eye-piece. The stage being then placed 
in the horizontal position, and the image being thrown up- 
wards, this latter is reflected horizontally by the prism, and 
is bent up by the tint-glass reflector to the eye. We believe 
the new camera will be found an extremely useful accessory 
by the working naturalist. 
Manual of Microscopic Photography. By Oscar Reichardt 
and Carl Sturenburg. Quandt and Handel, Leipzig, 1868. — 
This is an excellent little pamphlet, of some seventy pages, 
giving the necessary instructions and useful suggestions as to 
the art of photographing microscopic objects. Four illustra- 
tive photographs are given. The first is a cross-section of 
Hippuris vulgaris, and is magnified only l T 2 . Fig. 2 is a sun- 
picture of a bit of the tracheae of the silkworm caterpillar, 
magnified 4 - 2 . Both these photographs are intended to be 
examined with a lens. The two other figures are portions of 
P/eurosigma angulatum, one enlarged 3 ( l°o ) the other 87 T 50 . 
The original negatives were taken on collodion- albumen, and 
Gundlach’s glycerine-immersion objective No. 7 was used. A 
second enlarged picture was then taken. They appear to be 
satisfactory specimens, though not equalling some of Lieut. - 
Col. Woodward’s. Gundlach, of Berlin, sells a camera 
