1903. ] GEOGRAPHICAL DISTRIBUTION OF SPIDERS. 345 
as well as to the South-American and Afro-Mascarene forms, points 
equally forcibly to the peopling of Australia from either one or 
the other, or perhaps both, of the southern continents just 
mentioned, 
The remaining genera of Diplurine, namely, 7’rechona, Diplura, 
Harmonicon, Melodeus, and Uruchus, all of which are more 
specialised types than Brachythele and its allies, probably arose 
within their present area of distribution. 
A great contrast to the distribution of the Diplurine is presented 
by that of the Macrotheline. 
The occurrence of Macrothele in Spain, China, Burma and Java; 
of Porrhothele, which is scarcely separable from it generically, in 
New Zealand ; of Phyxioschema in the Transcaspian area; and of 
its near ally, Stenygrocercus, in Queensland and New Caledonia, 
suggests a southward migration of these types from the northern 
provinces of the Old World into Australia and New Zealand by 
way of China and Indo-Malaysia. Similarly /schnothele, a more 
specialised type than Jacrothele, perhaps descended from the north 
by way of India into Madagascar, South Africa, and crossed 
thence into South America, where with Hvagrus, which is also 
represented in South Africa, it is the only representative of this 
group of Dipluride. The entire absence from the Sonoran Region 
of forms related to Maecrothele, Hvagrus, and Ischnothele, is opposed 
to the supposition that the two last-mentioned genera had a 
northern origin in America. 
The Masteriz appear to be degenerate forms of the Macrothele. 
They are the smallest of all known Mygalomorphe, and are 
essentially eryptozoic or lucifugous, living in caverns or under old 
decaying vegetation in the dark, damp forests. Hence we can 
only pretend to a partial knowledge of then distribution, and it 
would be rash to draw deductions from the fact of their having 
been discovered hitherto only in Venezuela, the Philippines, and 
Upolu. 
The two genera of Atraces, Atrax and Hadronyche, confined to 
Australia, appear to be Macrothelinz specialised for a fossorial 
life, with which is correlated certain features imparting to them a 
superficial similarity to the Ctenizide. 
The Hexathele, resembling the Macrothele except in the 
retention of an additional pair r of spinning-maimille, undoubtedly 
a primitive feature, are confined, so far as is known, to New 
Zealand and Chili. There seems no reason to doubt that they 
passed from one of these countries to the other by a southern 
Jand-connection. 
Family PARATROPID® 
This family, specialised both in structure and habits, is repre- 
sented by three genera, Paratropis, Anisaspis, and Anisaspoides, 
confined to the Neotropical Region. Its affinities are doubtful, 
but some primitive genus of Dipluride allied to Brachythele must 
