78 PROCEEDINGS OF SOCIETIES. 
than the others. The second branch terminates in a similar but longer 
appendage. These curious appendages remind one very much of the toy- 
snakes, which consist of a number of saucer-like segments united at the 
middle. The fourth segment of the antenne also bears hairs at its 
extremity, two on one side and oné on tlie other; the latter much the 
shorter. Each of the three basal segments supports a pair of rod-like 
almost clubbed hairs, which are divided by a number of lines almost like the 
curious ringed appendages. These ringed hairs are no doubt connected 
with sensation. Between the two appendages of the branch is a small 
rounded body which is sessile in P. Hualeyi, and pedunculate in P. pedun- 
culatus, so named from that circumstance. 
The structure of the mouth appears not exactly to agree with that of either 
the chilopods or diplopods (Chilognatha.) The mandibles are distinct, some- 
what elongated, and have several teeth at the extremity. Besides these the 
other parts of the mouth have not been distinctly made out. Two pointed, 
unarmed, jointed appendages, may be supposed to correspond with the first 
pair of legs of Zithobius, or they may represent labial palpi; but, at present. 
their homology is obscure. 
The different views of naturalists respecting the position or 
value of the Myriapoda are then stated, and the author gives his 
reasons for adhering to the opinion of those who regard them as 
forming a distinct Class “separated from the other classes of 
Annulosa by characters of at least equal importance with those by 
which those classes are distinguished from one another.” 
Adverting to the remarkable fact that all Myriapods have at 
first three pairs of legs, and three pairs only; and that the same 
is the case among the Acarina, and that it might at first be 
supposed that these three pairs represented the six legs of insects, 
the author states that there is nevertheless a general agreement 
of opinion that these three pairs do not homologically represent 
those of true insects. At the same time the consensus is not so 
general as to what they do really represent. 
Nevertheless, the fact that centipedes commence life with no 
more legs than other Arthropods, and only acquire by degrees 
their most obvious characteristic, is very important; and as what 
is true of all the species may be reasonably concluded to haye 
been true of the whole group, we might have inferred @ priori 
that, although in the words of Newport, “there are never fewer 
than twelve segments and eleven pairs of legs in any genus of 
Myriapoda,” still there must have been at one time species 
possessing asmaller number of appendages. The genus Pawropus 
is, in fact, such a species, and possesses only nine pairs of legs. 
It tends, therefore, to a considerable extent to fill up the gap. 
With respect to the relations of Pawropus to the already known 
groups of Myriapods, it must be admitted that in some im- 
portant characteristics Pawropus closely resembles Scutiger. But 
the structure of the mandibles and of the legs shows that these 
resemblances are only analogical and do not indicate any close 
affinity. In fact, the Scutigeride are highly developed Chilopoda, 
which Pauropus is not. If, however, the existing Myriapods are 
descended from ancestors having a smaller number of segmentg 
