P.N.E.Z.C. 
76 GARMAN — CHIMZROIDS Vol. 11 
lorhynchus and Hfarriotta. In advanced stages the teeth of 
Hlarriotta differ from those of RAznochimera in possessing several 
series of tritors which in superficial aspect resemble, in shapes 
and arrangement, crowns of certain placodont teeth. On the 
teeth of RAimochimera there are no tritors; the teeth of the very 
young of the other living genera are similar; this no doubt is a 
mutual] resemblance to those of a common ancestor, an index to 
derivation. Not to mention further particulars, the forms of body 
being much alike, the new genus, established upon Harriotta 
pacyjica Mits., may be distinguished from Havriotta thus: 
Teeth without tritors, like the horny covers on jaws of reptiles and birds. 
Rhinochimera. 
Teeth with several series of tritors, like groups of placodont molars. 
FHlarriotta. 
On both of them the rostrum is very long and pointed; it is the 
more depressed, broadened and weak on Harriofta; it is the more 
compressed and strong on RAinochimera. Their family characters 
are such as not to permit of separating them from one another. Yet 
they differ so from the other genera as to make it necessary to estab- 
lish, under the name of Rhinochimeride, a distinct family for their 
inclusion. The shape of the body is much the same in all the living 
members of the group; for this reason the tendency is to throw 
them together, though the great differences between Chimera and 
Callorhynchus have not passed unnoticed. ‘These differences are 
really too great to admit of retention in a single family ; they neces- 
sitate separation into two, which increases the number of families 
of recent chimzroids to three. Without extending this article fur- 
ther than is needed to indicate the conclusions, and not to antici- 
pate more of general studies than of those of the genera, a sufficient 
array of the distinguishing characters may be indicated as below: 
Proboscis absent ; 
Lateral canal system sulcate ; 
Notochord with ringlike segments ; 
Hemispheres fused with olfactory and distant from optic lobes. 
Chimeride. 
