Arachnida, by R. T. Pocock. 63 



Two of them are immature, very thin, and of a semitrans- 

 parent white colour. The remaining specimen is full-grown, 

 with oblique olive-brown stripes above and a broad zone of 

 the same tint around the umbilicus. Beside the peripherial 

 keel, there are three others, somewhat finer, which encircle 

 the upper part, and the entire surface is finely spirally striated. 

 In general form they resemble Marten's figure 5, var. latilabris, 

 rather more than the figure of var. intermedia (fig. 4). 



8. Cassidida sulcidosa, Mousson, var. 



The form of this species occurring at Damma differs from 

 the type from Java and other localities both in colour and the 

 notch in the upper part of the labrum. These specimens are 

 of a very dark black-brown colour, with a single yellowish 

 line at the shoulder of the body-whorl, which is also of a 

 flesh tint at the base below the keel. The lip is also of a pale 

 reddish or flesh tint, but the notch at the upper part is very 

 slight, a meresinuation and not a decided sharp incision as in 

 the typical form. This variety also occurs at the Louisiade 

 Archipelago. 



9. Neritina corona, Linn., var. 



The specimens from Damma Island agree with the variety 

 figured by Reeve under the name of N. subgranosa, Re'cluz 

 (Conch. Icon. fig. 24) . This form also occurs at the Louisiade 

 Archipelago and the Philippine Islands. 



10. Septaria borbonica } Bory St. Vincent. 



The specimens collected by Mr. Walker appear inseparable 

 from this species, which is common to Mauritius, Madagascar, 

 and the neighbouring islands. The occurrence of specimens 

 at Damma agreeing precisely with examples from Mauritius 

 seems very remarkable, but 1 have already recorded an equally 

 interesting case of wide distribution in a species of the allied 

 genus Neritina, namely N. crepidularia. This species, which 

 is common in the delta of the Ganges, at Ceylon, the Eastern 

 Archipelago, &c, also occurs on the Gold Coast, West Africa. 



ARACHNIDA. By R. I. Pocock. 



Scorpions. 



Archisometrus mucronatus (Fabr.). 



This species ranges from Burmah, through Sumatra and 

 Java, to Celebes and Flores. 



