1883.) 19 9 (Packard, 
outer unequal long teeth; and within, a series of singular processes like 
stout sete: edged with dense spines on the inner side. This double appa- 
ratus of teeth and spinose processes, which may be called the pectinedla, 
gives the stipes a decided resemblance to that of the hexapodous maxilla. 
In the Chilopoda, according to the figures and description of Meinert, 
there is a greater variation in the nature of the pectinella of the stipes. 
As we have observed in the protomala of Scolopendra and Lithobius, 
there are three or more stout teeth, with an inner series of spinulated 
slender processes; but in several genera figured by Meinert, as Mesocan- 
thus’ albus Mein., Scolioplanes crassipes Koch, Ohetechelyne vesuviana 
Newp., @eophilus sodalis Bgs. and Mein., and Mecistocephalus punctifrons 
Newp., the cutting edge is provided with spinose processes alone. 
For the second pair of mouth appendages of the Myriopoda we propose 
the term deutomala, or second pair of jaws. They form the so-called 
labium of Savigny and later authors. In the Chilognaths they have a su- 
perficial resemblance to the labium of winged insects ; but the correspond- 
ing pair of appendages in Chilopoda are not only unlike the labium of 
Nexapoda, but entirely different in structure from the homologous parts 
in Chilognaths. The ‘“labium’’ of Newport, or first maxille of Meinert, 
have been described and figured by those authors, to whose works the 
reader is referred. 
‘The following remarks apply to the homologues of these parts in the 
Chilognaths. While most authors designate this pair of appendages as the 
‘Jabium,’? Meinert more correctly calls them the first maxille, briefly 
in the Latin abstract of his ‘‘Danmark’s Chilognather’’* in his diagnosis of 
the order describing them as ‘‘ Stipites maaitlares appendicibus instructi, 
detecti ;’’ but in his description of Julus referring to them as ‘ Lamina la- 
bialis parva, stipites labiales modo partim sejungens.”’ 
Meinert aiso describes what he designates as a third pair of mouth-parts, 
or labium, which is enclosed by the second pair, behind which is a trian- 
gular plate (Lamina labialis) which he regards as a sternal part, correspond- 
ing to the mentum of insects. He then adds: ‘‘In front of the labium 
in the Polydesmide are two short round styles (stilt linguales), which are 
toothed at the end.’? He also speaks of the curved piece behind the 
laminia labialis, which he designates as the hypostoma (see our fig. 2). 
It should be observed that Savigny states that the labium (lévre infévi- 
eure) isin Julus composed of what he designates as the first and second 
maxille ; his second maxille being Meinert’s labium. 
It seems to us that the researches of Metschnikoff+ on the embryology 
of the Chilognaths (Strongylosoma, Polydesmus and Julus) leave no 
doubt that these myriopods have but two pairs of mouth-appendages, 
which Metschnikoff designates as mandibles and labium. The latter 
arises as a pair of tubercles or buds, at first of exactly the form of the man- 
*Naturhistorisk Tidsskrift. 8 R. 5 B. 
tEmbryologie der doppeltfussigen Myriapoden (Chilognatha), Von Elias 
Metschnikoff. Zeitschrift far Wissenschaft. Zoologie, xxiv, 253, 1874. 
