15 
10 
Number 
Length (x). 
HYALONEMA (PRIONEMA) CRASSUM. 281 
fall into two groups, large and small ones. These two groups are very clearly 
distinguished, there being no amphidiscs 62-159 » long. This absence of inter- 
mediate amphidiscs finds its expression in the adjoined graph in the large gap of 
the curve between 72.89 and 129.13. The amphidiscs the lengths of which are 
represented by the curves to the right of the gap belong to the morphological 
groups 1 and 2. The two curves overlap considerably. The amphidiscs to 
Smooth \ Mtacramphidiss 
-—----—-- Serrated 
poconscreseese Micramphidiscs 
Micramphidiscs Macramphidiscs 
———_ AS oor "eo Oo 
Small Large Serrated 
oe i 
Smooth 
—_——_- 
--4-----/--------------- 
--------;--- po np rt rt nn ee tenes: 
' ' 
' ra 
' i] 
~ u yal - 
See a= eee pee ee eee ere a Se eR eee ow ales Ses em omen eee 
ai 1 A 
se SS a eT ee 
fibene atin 
Bie ate it 
cf es fie a ' 
ecient eaten ened a ae hed ap a ee SRS ta Tae ey Ta EOS RPE Ee a ee 
Be rhea ' 
== ma et as a i 
pod Oe heen aii 
mart Ze 
eet a a a ae Soi ae Se oa ey ol ee eee eee Ne a = 
Hee cae Sie! ies eat ee alee ra 
ee nnrE Pen Me ee ee ee atl 2 Ne ee ns Se is 
a NS ES A+ 
: He ihe Se i aa ass : 
a a a a ag eh ein 
ON SCN DHANMOnTDAOCOoHOMWMWOMODWOAAO DTW & 
AY OPYHANHAASTAANREANQTAASCHRASCNH 
NYT MO HMAMMNDNMOOOHEOTrMODAtTOONCWOHeROM-ONO HH 
An AH ANNAN YOM THT MOOONRDARDOAAN TOL 
| | eee 
1 
pre lt tok EP I we okt lel 
OADNGMOAAMNDNOCHDOYHTODOAORMWDOAANINYNYTWHM 
BN MOM AANMAROTMIANREAANAMANSCHE OMASCN 
Ae HMO OHMNMNOODWOHAHAKO HNO DADONOCALKR OFAN WS 
al OT St PIV ISRIUSN TNINS OSC G.e) sists stl ill Doda SS) SoTL GeO) i2 SOP ASS Kes NI oy Ze 
Fig. 13.— Amphidises. 
which the curve to the left of the gap pertains are those of the morphological 
groups 3 and 4. There is a conspicuous depression in this curve at 37.40- 
41.14, corresponding to the absence of amphidiscs 37-41 » long. This depres- 
sion may be taken as the limit dividing the (smaller) amphidises of the mor- 
phological group 4 from the larger ones of group 3. 
