304 
Fig. 50. Pachijlasma 
scutistriata from 38° 12’ 
S., 149° 40’ E. a mand- 
ible, b maxilla. [x22]. 
most quite even, only with a faint pit for the adductor. The artic- 
ular ridge is rather long, but little prominent. 
Tergum has an almost invisible indication of aspur. Extern- 
ally there is a feeble, longitudinal depression, and the lines of 
growth are very faint. Internally fine crests are present for the 
adductor; the short articular ridge is very pro¬ 
minent and strongly projects beyond the scutal 
margin. 
The size of the specimens varies greatly; 
the smaller specimen basally has a rostro-car- 
inal length of 7,5 with a carinal height of 3 mm, 
the largest specimen in the same way has a 
length of 20 mm and a carinal height of 15 mm. 
In its internal features the mouth parts 
of the animal show the typical C h ta mal id. 
The labrum has no teeth nor hairs; it is not 
bullate, and has neither notch nor median grove. 
The man di ble (Fig. 50 a) has three teeth, 
the second situated at the middle of the cutting edge. The upper 
edges of the second and the third tooth are basally finely pectinate. 
The lower angle of the mandible is armed with rather long bristles 
which take the place of the usual pectination. Only few finer hairs 
are present in the lower part of the blade. 
The maxilla has a very strong upper spine; between this 
and a sharply defined notch three or four shorter spines are situ¬ 
ated. Below the notch the median third of the cutting edge is 
armed with four or five pairs of strong spines, and below these 
spines the edge again carries shorter spines, among which one 
stouter and more prominent. The sides of the blade are covered 
with fine hairs near the cutting edge. 
The armature of the c irri displays two types. In cirrus I and 
II the segments are bullate, and armed with numerous spines in 
transverse belts. In cirrus IV to VI the segments have three pairs 
of long and strong spines, and basally some few fine hairs on their 
anterior side; distally 5 — 6 long hairs are present on the posterior 
side of the segments. 
In cirrus III the basal segments of the rami are armed in the 
same way as in cirrus I and II; the greater majority of the seg- 
