ol2 R. Lydekker—WNote on the Tehthyopterygia. 
26. IcuTHYOSAURUS TRIGONODON, Theodori. Up. Lias, Bavaria. 
TI]. Genus Mrxosaurus, Baur. Humerus articulating with the 
radius and ulna, which are elongated and separated by an 
interval. 
27. Mixosaurus cornattanus (Basani). Up. Lias, Italy. 
Syn. Ichthyosaurus cornalianus, Basani. 
The forms indicated by the under-mentioned names cannot be 
classified, and it is probable that several of them are synonyms of 
those already mentioned. 
28. Ichthyosaurus equalis, Phillips. Kimeridge Clay, England. 
ZO rae »  angustidens, Seeley. Up. Chalk, England. 
Oe rhese a (?) atavus, Quenstedt. Mid Trias, Germany. 
5) oA », australis, Hector. (?) Trias, New Zealand. 
(?) = Mixosaurus. 
SB sys ,,  calorodirus, Seeley. Kimeridge Clay, England. 
SOwe hiss » (2) carinatus, Sauvage. Up. Trias, France. 
? = Mizxosaurus. 
S47 4) »  coniformis, Harlan. ? Lias. 
SOM »  erassicostatus, Theodori. Up. Lias, Bavaria. 
SOMME. »,  gaudensis, Hulke. Reputed Miocene, Malta. 
Sais »,  hexagonus, Theodori. Up. Lias, Bavaria. 
»  hygrodirus, Seeley. Kimeridge Clay, England. 
SOA he »  imgens, Theodori. Up. Lias, Bavaria. 
AlN fae 5  macrophthalmus, Theodori. Up. Lias, Bavaria. 
7) ah aN »  megalodirus, Seeley. Oxford Clay, England. 
AD 93 »  Nordenskisldi, Hulke. Trias (?), Spitzbergen. 
Ar il iiss »  planartus, Theodori. Up. Lias, Bavaria. 
44. ,, » polaris, Hulke. ‘Trias (?), Spitzbergen. 
45. ,, » (2) rheticus, Sauvage. Up. Trias, France. 
(?) = Mixosaurus. 
AG Lat 35 »  triscissus, Quenstedt. Up. Lias, Wiirtemberg. 
The name I. latimanus, as will be noticed below, must be discarded. 
The names I. Bonneyi, I. Doughtyi, and I. platymerus, Seeley, and 
I. advenus, Phillips, are merely MS. ones; the first three being 
applied to specimens from the Cambridge Greensand, and the fourih 
to vertebrae from the Stonesfield slate. J. Walkeri, Seeley, hag been 
made the type of Cetarthrosaurus. 
In regard to the two new species above mentioned Onhihalmon ag, us 
cantabri igiensis is founded on a small humerus from the Cambridge 
Greensand in the British Museum (No. 43989), which differs from 
that of O. icenicus in having the three distal facets of nearly equal 
dimensions. The name Ichthyosaurus Conybeari is applied to an 
imperfect skeleton of a small Ichthyosaur in the same collection (No. 
38523) from the Lower Lias of Lyme-Regis, which differs from 
I. communis in the notching of the anterior border of some of the 
phalangeals of the pectoral limb, and in the relatively longer skull ; 
while it is distinguished from I. intermedius by the greater width of 
the pelvic limb.. It is possible that I. latimanus, Owen, may be 
