342 
ACTINOPIEPvTGII, 
The small fish named Anguilla hrevicula by Agassiz (IS^eues 
Jahrb. 1835, -p. 307, and ojo. cit. vol. v. pt. i. p. 15, pt. ii. p. 134, 
pi. xliii. fig. 1), from Monte Bolca, may also belong to Eomyrus. It 
is not represented in the Collection. 
Genus RHYNCHORHINUS, novum. 
\_ex. Agassiz, Poiss. Poss. vol. v. pt. ii. 1844, p. 139 (name only).] 
An imperfectly definable genus, known only by the head, which 
closely resembles that of Eomyrus but appears to have a stouter 
rostrum. 
Rhynchorhinus branchialis, sp. nov. 
[Plate XVIII. fig. 4.] 
1844-45. Ehynchorhinus branchialis, L. Agassiz, Poiss. Foss. vol. v. 
pt. ii. p. 139, and Rep. Brit. Assoc. 1844, p. 308 (name only). 
Type. Abraded hinder portion of skull and mandible ; British 
Museum. 
The type species, with skull about 0’05 in length. Vidth of 
occiput equalling about one third the total length of the cranium ; 
length of coronoid region of mandible exceeding half that of the 
dentary border. 
Form. Log. Lower Eocene: London Basin. 
P. 633. Type specimen, very imperfect and much abraded, com¬ 
prising the hinder half of the cranium and mandible, both 
hyomandibulars, and part of the left preoperculum; 
London Clay, Sheppe}’. Egerton Coll. 
P. 163. Slightly smaller abraded skull and mandible of the same 
type, shown in right side-view and from above of the 
natural size in PI. XVIII. figs. 4, 4 ct; Sheppey. The 
• occipital region is shortened by abrasion; but the limits 
of the parietals (pa.)^ extending as far forwards as the 
postorbital prominence, are shown. The squamosals {sq.) 
are extremely attenuated and produced in front. The 
anterior ends of the frontals (/r.) are excavated in a 
sharp re-entering angle where they articulate with the 
relatively large mesethmoidal rostrum {eth.). The much 
expanded hyomandibular (Jim.) is well preserved ; and 
the mandibular articulation is directly beneath the post¬ 
orbital prominence. The coronoid region of the man¬ 
dible is relatively large ; and the only well-preserved 
