370 MOSTLY MAMMALS 



shield-like carapace, upon the upper surface of which are 

 carried a variable number of simple eyes, one pair of which 

 is larger than the others, and is placed dorsally, while the 

 smaller ones are marginal. The first pair of appendages are 

 modified into short nipping claws, while the jaw-appendages, 

 technically known as maxillary palpi, are greatly enlarged 

 to form the huge pair of pincers carried on each side of the 

 head ; and the four pairs of walking legs are supported by 

 the first four segments of the thorax. It is important to 

 add that by means of lung-sacs opening by four pairs of 

 apertures on the sides of the abdomen, scorpions breathe 

 air, and it is accordingly only in rocks of fresh-water 

 origin, or such as were deposited near the shore, that their 

 remains are likely to be preserved. 



According to the most recent classification, existing 

 scorpions are divided into four families, of which the first 

 two are again divided into several sub-families. An im- 

 portant feature in this classification are the so-called " pedal 

 spurs," which are found upon the articular membrane con- 

 necting the foot, or terminal segment of the legs, with the 

 segment that precedes it. The Scorpionidae, or typical 

 scorpions, have only one such spur, whereas two are present 

 in the other three families. It will be unnecessary to further 

 consider the classification of the group in this place ; but 

 it is important to notice that one of the sub-families of 

 the Scorpionidae is confined to Africa south of the Sahara, 

 and the Indian and Malayan countries ; while another has 

 representatives not only in those regions, but also in 

 northern South America and Australia. At the present 

 day, indeed, scorpions are found in Europe only in the 

 more southern countries, where the majority of the species 

 are of comparatively small size ; and it is in the tropical 

 and sub-tropical regions of the globe that the group attains 



