86 
Guide to Arachnida. 
Table- 
cases Nos. 
19 , 20 . 
has been introduced into all the warmer regions of the world, and 
is found in oceanic islands. 
Scorpions are carnivorous, feeding chiefly on insects. As is 
well-known, they are poisonous; the poison glands, which are 
paired, are situated in the terminal bulb of the tail. The larger 
species mostly construct deep burrows with their pincers, others 
live in shallow excavations under stones or under the hark of 
fallen trees. 
A representation of the burrows of the common Egyptian 
scorpion ( Buthus quinquestriatus) is placed in Wall-case 7. 
The young of scorpions are born fully formed, but in some 
species at least they are still enclosed within the egg-shell at birth 
and are liberated by their mother or by their own efforts. Until 
they are able to shift for themselves they are carried about on the 
back of the mother; a female example of a South American 
scorpion ( Centrums margaritatus), carrying its family on its back, 
is exhibited in Table- case 19. 
The classification of the scorpions is still in an unsettled state ; 
the recent species are arranged by Mr. Pocock in four families : 
1. Pandinidae. 2. Bothriuridae. 3. Vejovidae. 4. Buthidae. 
A representative series of scorpions is displayed in Table- 
case 20. 
Fam. 1. — Pandinidae. 
This family, which contains the largest of the existing 
scorpions, is found in Africa, South Asia, Australia, and South 
America. It is characterised by having the sternum of the 
cephalothorax pentagonal in shape, and by the presence of only 
a single pedal spur upon the feet. (Genera : Pandinus , Opistlioph- 
thalmus , Urodacus, etc.) 
Fam. 2. — Bothriuridae. 
This family is confined to South America and Australia. It is 
characterised by having the sternum strongly compressed antero- 
posteriorly, and reduced to a short but wide transversely-lying 
plate. There are two pedal spurs on the feet. (Genera : Bothri- 
urus, Cercophonius, etc.). 
Fam. 3. — Vejovidae. 
The representatives of this family are found in South Europe, 
Asia, and North and South America, but are entirely unknown in 
