FASCICULI MALATENSES 
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called ulat jelbtong^ because their colour is supposed to resemble that of the 
monkey known as Ibtong {Preshy tes ohscurus'). The confusion is to some extent 
justified by a certain resemblance in form, in the apparent texture of the 
integument, and in type of coloration, though the dorsal surface of the 
commoner species of the Molluscan genus is dark slatey blue, while that of 
the Peripati found in the Malay Peninsula is chocolate brown. The move- 
ments of the two genera, widely separated as are their organs of progression, 
are not so dissimilar to the eye, especially in the uncertain light of the jungle, 
as might be expected, and on one occasion I was quite deceived myself, 
exclaiming that we had found Peripatus at last on seeing Atopos moving, with 
some rapidity, across a jungle path in the early morning. Slugs of the genus 
under discussion are frequently found in the centre of rotten tree-trunks, in a 
dry, stiff, retracted, and apparently torpid condition, and though Eoperipatus is 
found in very much the same environment, the retraction of the molluscs’ 
tentacles reduces their resemblance to the Arthropod to a minimum. Both 
Peripatus and slugs resembling it are said by the Malays to be so poisonous 
that if a drop of their slime, which is very scanty in the latter, and is, of course, 
ejaculated from certain large glands in the former, falls on a man’s limb it will 
cause it to rot off. The slugs are sometimes calcined and their ashes rubbed 
on the horns of fighting bulls, under the belief that even a scratch from a horn 
so treated will cause the bull’s opponent to fall down dead.’ N.A. 
The distribution of Atopos in the Malay Peninsula seems very anomalous. 
The genus was originally described from the Philippines, and species referred 
to it are also known from Amboina, Celebes, West Sumatra, and Cochin 
China, while several species beside the present one have been described from 
the Eastern Malay States.’ But curiously enough, with the exception of one 
from Penang (and this locality, like that of ‘ Malacca,’ often covers a very 
wide area, indeed), no species has ever been met with on the western side of 
the Peninsula. The State of Perak has been fairly well explored by mala- 
cologists, and if they existed it is highly improbable that such large and 
conspicuous forms as the species of Atopos are would have escaped notice. 1 
searched for them myself in environments precisely similar to those in which 
they were found on Bukit Besar, but in every case without success. 
A parallel instance may be mentioned among birds, for the barbet, 
Thereiceryx lineata (Viell), is known from the Burmese countries, Siam, 
Cochin China, Patani, and Pahang, reappearing in Java, but has never been 
met with on the western side of the Peninsula. — H. C. R. 
1. Collinge, Journ Malac.y IX, p. 87 et seq. (1902). The genus has recently been found in North-west Borneo, 
See Journ. Malac. X, p. 82 (1903). W. E. C. 
