944 Transactions, —Zoology. 
The Black Spider-wasp of New Zealand, like many of its congeners, is 
an accomplished builder in clay. On this account it is generally known as 
the * Mason Bee;" but this name is wrongly applied, inasmuch as the 
Mason Bees (Osmia) form a very distinct section of themselves. They also 
construet clay houses with much skill and ingenuity, or form tunnels and 
burrows underground, but, like true and orthodox bees, they lay up a 
supply of pollen or honey in their cells for the nourishment of their larve. 
The nest which I have now the honor to place before the Society, and a 
vertical section of which is shown in the accompanying sketch (Fig. 1, 
Plate III), is a fair sample of the way in which the Black Spider-wasp con- 
structs a habitation for her family. The masonry is firm and compact, the 
walls as well as the interior partitions, dividing one cell from another, 
being formed of yellow clay, which hardens by exposure to the atmosphere. 
The exterior surface is finely corrugated, or covered with minute stris, 
presenting a vermiculated appearance; and the whole structure, before 
being closed up and hermetically sealed, is very neatly finished. On open- 
ing the nest by making a longitudinal cutting, it is found that each cell, 
which is eompletely shut off from the adjoining ones, contains one or more 
spiders, not lifeless but apparently in a state of unconscious torpor, and 
performing their last offices in the economy of insect-life, which is pa- 
tiently to await the hatching of the parsitie grub, and then to supply the 
larder with their own bodies. I have not been able to watch the hatch- 
ing operations of this insect; but, judging from what we know of its allies, 
we may, I think, conclude that the Spider-wasp deposits its egg in or upon 
the body of its victim ; that the larva hatches out in due time, and then 
feeds on the spider till it has attained its full size, when it spins itself a 
thin integument, or cocoon, and remains in an inactive state until the 
following Spring, when it completes its transformations. 
In the specimen of the nest now exhibited, the cocoon stage has been 
reached, and of the original spider-stores nothing is left but the shrivelled 
remains. This nest was taken on the last day of October, from the outer 
wall of a house on Wellington Terrace. It was found, among many others, 
in the wall-chinks, behind a verandah-panel, the situation having become 
exposed in the course of necessary repairs to the building. The cocoons 
are sometimes oval, sometimes elliptical in form, and of a yellowish-brown 
. eolour. 
The spiders eaptured and stored in the manner mentioned are not killed, 
but are rendered insensible by the injection of some occult poison from the 
body of the Wasp. The sting of the insect appears to penetrate the nervous 
centres, and to paralyze the victim without depriving it of life, so that it 
may exist in a comatose or torpid state for many weeks, or till required to 
