376 Geological Society. 



species with all those described, Sir Philip Egerton considers they 

 approximate more nearly the species of the lias than those of the 

 greensand, and infers from this zoological evidence that the Giffoni 

 beds belong to the former. 



2. Semionotus pustulifer, Egerton. — Fish large; operculum arenated; 

 humerus and scapula pustulated ; scales thick and lustrous ; surfaces 

 slightly uneven ; upper and lower margins deeply undulate. Stratum, 

 Lias ; found with last. Cab. Egerton. 



3. Semionotus minutus, Egerton. — Fish small; body slender; cau- 

 dal pedicle thick ; scales extended over the upper lobe of the tail. 

 Stratum, Lias ; found with last. Cab. Egerton. 



4. Lepidotuspectinatus, Egerton. — -Fish oblong, subfusiform; length 

 9 inches ; depth 2§ ; head small ; fins small ; scales marked with 

 delicate radiating striae ; posterior margin finely pectinate ; upper 

 edge convex, lower one concave ; dorsal, anal and caudal scales 

 rhomboidal, with entire margins. Stratum, Lias. Locality, Whitby. 

 Cab. Enniskillen. 



5. Pholidophorus Hartmanni, Egerton. — Size of Pholidophorus 

 latiusculus. Head rounded ; orbit large ; upper angle of operculum 

 striated ; preoperculum marked with few moniliform inequalities ; 

 humerus plicated ; scales small, serrated on the posterior margin ; 

 its serrations decrease in number and increase in size on the pos- 

 terior parts of the body. Stratum, Lias. Locality, Ohmden, in Wur- 

 temburg. Cab. Enniskillen, Egerton. 



6. Pholidophorus crenulatus, Egerton. — Rather larger than Pho- 

 lidophorus latiusculus. Head rather pointed; humerus obliquely 

 plaited ; pectoral fins large, with 22 rays ; caudal fins strong ; the 

 upper lobe bordered full two-thirds of its length with fulcral scales ; 

 rays 28 — 30 ; scales ribbed vertically on their bases, furrowed hori- 

 zontally on their exposed surface, and crenulated on the posterior mar- 

 gin ; the ventral scales deeply incised. Stratum, Lias. Locality, Lyme 

 Regis. Cab. Egerton. 



June 21. — The following papers were read : — 



1. " Supplement to a Memoir on the Fossil species of Chimara." 

 By Sir P. Grey Egerton, M.P., F.G.S. 



Since the author's former memoir was communicated to the So- 

 ciety*, he has seen in the collection of Mr. Dixon a new and striking 

 addition to the genus Ischyodus. The specimen is from the chalk 

 of Southeram, and presents two dental plates only slightly dislocated 

 from their natural juxtaposition. At first sight these would appear 

 to be the dental armature of the lower jaw, corresponding nearly in 

 size to the lower mandibles of Ischyodus Mantelli. A closer exami- 

 nation has satisfied Sir Philip Egerton that they are in reality the 

 intermaxillary plates of the upper jaw of a most gigantic chimeeroid. 

 They exceed in size the corresponding teeth of Ischyodus Toumshendi, 

 the largest species hitherto found, by one third. As compared with 

 the intermaxillaries of that species they are broader, more compressed 

 and less robust in antero-posterior diameter, and less hooked at the 



* An abstract of Sir P. Egerton's former memoir has appeared in the 

 present volume, p. 51. — Edit. 



