490 DR. W. G. EIDEWOOD UN THE CRANIAL [Dec. 13, 



Not one of the eleven genera iinclei' consideration has parasphe- 

 noidal teeth, and only Coilia, Dussvviieria, Clnpea harenyus, and 

 Clupea sprattus have teeth on the vomer. 



The post-temporal hone has an epiotic limb in all, and a dee}» 

 or opisthotic limb in all but Coilia. In Ghatoessas the union 

 between the post-temporal bone and the epiotic is more of the 

 nature of a synovial articulation than a ligamentous con)iection. 

 The supratemporal bone is of the same character in all, and in 

 all but Coilia the sensory canal that it carries is triradiate. A 

 subtemporal or supi'aopercular bone is present in Chcmos. 



The nasal bone is small and loosely embedded in the skin, and 

 there are fi-om five to eight bones disposed around the eye. In 

 Chatoessus and Chanos the premaxilla bounds the upper border of 

 the mouth ; in the othei- nine genera the gajae is bounded above 

 by both premaxilla and maxilla, although in Pristigaster and 

 Hyperlophibs the maxilla takes but a small share. In Chirocentrtis, 

 Clicpea, Fellona, Pristigaster, Dussumieria, Bngrmdis, and Coilia 

 both maxilla and premaxilla beai' teeth, although in Pellona the 

 teeth are vestigial : in Pellonala the premaxilla bears teeth, but 

 not' the maxilla ; in Chanos, Chatoessus, and Hyperlophus 1)oth 

 premaxilla and maxilla are edentulous. The premaxilla is firmly 

 united to the maxilla by fibrous tissue in Chiroceiitrus. Two 

 svirmaxilla? ai'e pi'esent on each side of the head in all but Uyper- 

 lo'phas, Chatoessus, and Chanos ; Hyjierlojihus and Chatoessus have 

 one, and Chanos none. 



The angular is a distinct bone in all but Enyraulis and Coilia. 

 The endosteal part of the articular can be recognised, but in no 

 case is it separate from the ectosteal part. A small sesamoid 

 articular is found in CMrocentrus, Clapeajinta, and Chanos. 



The hyomandibular articulates with the cranium by two heads in 

 Clupea jinta, Hyperlophus, Chatoessus, Dussumieria, and Engraulis, 

 and by a single head in Chiroceiitrus, Clupea harengus, Pellona, 

 Coilia, and Chanos. In Coilia the single head present is probably 

 equivalent to the anterior of the two heads found in Engraulis. 

 In Chanos alone of the genera under consideration is the quadrate 

 sepai-ated from the symplectic and metapter3^goid. Teeth are 

 boi-ne by the palatine bone in Chirocentras (4 or 5 minute teeth), 

 Clupea sprattus (a row of teeth), Clupea harengus (2 or 3 minute 

 teeth), Pellona, Pellonula, Pristigaster, Dussumieria, Engraulis, 

 and Coilia ; the palatine is edentulous in Chanos, Chatoessus, 

 Hyperlophus, and Clupea Jinta. The ectopterygoid is toothed in 

 Pellona, Dussumieria, Engraulis, and Coilia, but not in CMro- 

 centrus, Clajyea, Pellonula, Pristigaster, PLyperlophus, Chatoessus, 

 and Chanos ; the entopterygoid is toothed in Clupea spratttis (a 

 few teeth), Pellona, Pellonula, Pristigaster, Dussumieria, and 

 Engraulis, but not in the other forms examined. 



The branchiostegal rays are most numerous in Z>»6■s^^??^^e;■^a (13), 

 Engratdis (11), Coilia (11), aiid are fewest in Chanos (4). CMro- 

 centrus has 8, Clupea 7 or 8, Chatoessus 6, Hyperlophus 5. 

 The interhyal is bony in all, except, perhaps, in Chanos. In all 



