THE ONYCHOPHORA OF WESTERN AUSTRALIA. 
45 
relation to Peripaloides gilesii, 1 asked Professor Spencer for the 
loan of the type specimens of that species, and he very kindly 
sent these, together with a microscopic preparation of the jaws. 
Dimensions.- According to Bouvicr, the length of his 
specimens varied from 10.5 mm. to 21 mm. This is stated by 
him to be almost the size of Peripatoid.es orient alts and a little 
larger than Peripaloides oceidentalis. 
Spencer’s specimens of P, gilesii measured 22 mm., 25 mm., 
and 27 mm., respectively. The discrepancy in size means nothing, 
for in Bouvier’s case the individuals were preserved and contracted. 
Mv specimens from Mundaring Weir ranged in size from 12 mm. 
to 34 mm. The length of 34 mm. was that of the largest when 
outstretched and walking. On being touched it contracted to 
28-30 mm., and on fixation it diminished still further to about 
22 mm. It is obvious, therefore, that one must be careful in 
deducing any differences from dimensions. 
Colour. — The colour of the Mundaring Weir specimens 
agrees with that of the l’eripatoides described by Bouvicr, and 
Spencer’s description is also similar. 
Mandibles. -The mandibles are accounted as one of the 
chief diagnostic features of the species P. gilesii. According to 
Spencer, the first jaw is simple in all specimens, without any 
accessory tooth. The second jaw has four clearly marked and 
one minute accessory tooth. Bouvicr states that “ I.es mandibules 
sont depourvues de dents accessoires sur leur lame externe, 
comrne dans les Peripaloides Suteri, P. Novae Zeylandiae et 
oceidentalis , et contrairement a ce que l’on observe dans le Pen- 
patoides orientalis ; leur lame interne presente 5 dents accessoires.'’ 
There is absolutely no difference between the jaws of Spencer's 
specimens, those described by Bouvier, and my specimens from 
Mundaring Weir. 
The description of the mandibles given by Bouvier is not 
quite correct, for in some specimens the number of accessory 
teeth is more than five. 
Legs.— The number of claw-bearing legs is perhaps the 
most important character in the diagnosis of the species P. 
gilesii and P. woodwardi. Both Spencer and Bouvier state that 
the number suffices to distinguish their species from all other 
Australian forms except Peripaloides Suteri. I hey both, however, 
give the same number, sixteen ! Ihus so far as the supposed 
characteristic features are concerned, the specimens of Spencer 
and Bouvier are identical. Spencer’s paper was published some 
months before that of Bouvier and consequently the name P. 
rnodwardi must be rescinded. The Peripatus of the Darling 
Range, recorded from Armadale, Lion .Mill, Mundaring Weir, etc., 
is Peripaloides gilesii, Spencer. 
