METHODS OF STUDYING THE ANNELIDA. 307 
slightly warmed, has placed on its surface a large drop of a care- 
fully-filtered solution of shellac in absolute alcohol ; the drop is 
caused to run over the whole surface by tilting the slide, or is 
spread over by means of a glass rod, and the superfluous fluid is 
drained off. In this way the slide is covered with a thin trans- 
parent layer of shellac. Before use the surface of the slide 
(slightly warmed) is gently pencilled over with clove oil. When 
the sections have all been placed on the slide, it is placed over a 
water-bath heated to about 130° Fahr., until the smell of clove 
oil can no longer bedetected. It is then allowed to cool, and the 
surface flooded with turpentine, or a mixture of I part of carbolic 
acid to 3 of turpentine, to dissolve the paraffin. If turpentine 
alone is used, it will be found advisable to replace it with clove 
oil after the paraffin is dissolved out, before mounting in balsam 
or dammar. I find it a great saving of time, trouble, and space 
to place the sections in order along the slide in two rows, about 
30-50 in each row, and to cover each row with a single long slip 
of thin glass about half an inch broad and about an inch shorter 
than the slide. The slips are laid on after the paraffin has be- 
come thoroughly dissolved out and the sections have cleared up, 
and the balsam in a thin solution is run in at the sides, 
For the finest sections the shellac method described above, 
in which the object must be cut dry, is not very favourable. 
These are better cut in many cases with the aid of a large drop 
of sweet oil to cover the surface of the object and the portion of 
the knife with which it is being cut. When the sections are 
very delicate and brittle, they must be floated on the oil from 
the knife to the slide; the superfluous oil must then be drawn 
off with bibulous paper, and the paraffin dissolved out as before 
with turpentine. There are many cases, however, in which the 
finest sections can be made without the aid of the oil, and 
it is well to do without it when possible, as it is somewhat diffi- 
cult to dissolve away from the sections, and sometimes delays 
their complete clearing up. 
ON A MARINE CADDIS-FLY FROM NEW ZEALAND* 
(Philanisus, Walker, =Anomalostoma, Brauer). 
<> 
BY R. MCLACHLAN, F.R.S., F.L.S., HON. MEMB. N. Z. INST. 
eee ees 
In April of this year I received a letter from Prof. F. W: 
Hutton, of Canterbury College, Christchurch New Zealand, in 
which was the startling announcement that the larva of a Caddis- 
fly lives habitually in rock-pools, between high and low water- 
marks, in Lyttleton Harbour in that colony, and forms its case 
of coralline seaweed. Hehad often attempted to rear the perfect 
—————’ 
*Read before the Linnean Society of London, 15th June, 1882. 
