1879.] ARACHNIDA FROM MADAGASCAR. 731 



each side beyond the blackish bands clothed with depressed 

 whitish pile ; palpi, excepting the bulbus and under surface of body, 

 horn-yellow ; bulbus castaneous, clothed with pale brown hair above, 

 black below ; falces castaneous, clothed with pale hair ; legs sparsely 

 clothed with pale hair and with black spines ; abdomen above brown, 

 densely clothed with short pale greyish-brown hair. 



Cephalothorax ovoid, truncated in front, very slightly indented 

 in the middle behind, shelving at the sides, but flattened along the 

 dorsal or central longitudinal region ; sutural outline of the caput 

 feebly indicated ; margins of cephalothorax behind the caput regu- 

 larly convex ; abdomen oval, flattened or truncated in front, posterior 

 extremity obtusely pointed ; pectoral shield oval and indistinctly 

 nine-sided; coxa? barrel-shaped, those of the two anterior pairs of 

 legs with straight anterior and convex posterior margins. Relative 

 length of the legs 1 and 4, 2, 3; relative length of joints as follows: — 

 femoral joints — first pair 8| millimetres, second pair 7, third 6, fourth 

 8 ; tibial (including basitibial or knee-joint) — first pair 11, second 9, 

 third 7, fourth 11; tarsal joints or tarsus— first 13|, second 11 J, 

 third 9, fourth 14. Falces large, with three conical denticles on the 

 inferior margins, and with a powerful curved movable fang; palpi 

 about 9 millimetres in length, with the bulbus large, pyriform, and 

 incurved. Length of cephalothorax and abdomen together (exclusive 

 of falces) 1 7 millimetres. 



Antananarivo {Kingdon) . 



2. Gasteracantha borbonica, Vinson. 

 Antananarivo {Kingdon). 



3. Gasteracantha acrosomoides, Cambridge. 

 Antananarivo {Kingdon). 



4. Ccsrostris tuberculosa, Vinson. 



Fianarantsoa {Shaw). 



Unfortunately these specimens were allowed by the collector to get 

 nearly dry and were injured by mould. 



5. Ccsrostris mitralis, Vinson. 



Antananarivo {Kingdon). 



One specimen, agreeing well with the figures. 



6. Ccsrostris stygiana, n. sp. (Plate LVIII. figs. 4, 4 a, 4 b.) 



2 ■ Cephalothorax black, covered when dry with golden pile, 

 posterior portion castaneous ; legs above black, banded at base of 

 tibiae and tarsi with white ; coxae and femora below castaneous ; falces 

 black, fringed above with golden hair ; maxillae orange above, dark 

 castaneous, fringed with dull lake-red hair, below ; labium and 

 pectoral shield blackish ; abdomen above testaceous, below black. 



Cephalothorax nearly square, but convex at the sides, almost per- 

 pendicular behind the caput ; the latter more than twice as wide as 

 long, with six projecting horizontal processes or prominent tubercles, 



