4. GOBIESOX. 501 



sliglit contractions, internally by broad and prominent circular folds • 

 The oesophagus has longitudinal and very elevated folds, some of 

 which are continued into the stomach ; the latter is short, globular, 

 and separated from the small intestine by a thick vahula pylori. 

 Pyloric appendages none. The numerous folds of the small intestine 

 are longitudinal, or oblique, and short, whilst those of the rectum are 

 transverse. A valvida, not so thick as that on the pylorus, at the 

 commencement of the rectum. 



The liver is large, situated on both sides of the stomach, both 

 halves being united bj' a very narrow bridge over the cardia ; the 

 left half is bilobed. The gall-bladder is rather large, pear-shaped, 

 and not attached to the Uver. A very remarkable circumstance is 

 the presence of a broad, well- developed omentum, in which fat is de- 

 posited as in mammals. I am not aware that it has been observed 

 in other osseous fishes, except in a rudimentary state in very young 

 si)ecimens. 



The kidneys are very slender and thin, situated along the whole 

 length of the abdomen on both sides of the vertebi-ae ; the ureters 

 lead into the hindmost extremity of the imne-bladder, which is 

 elongate, cuneiform. Testicles separated from each other. 



Sl-eleton. — The form of the skull is intermediate between that of 

 Chorisochismns and Sici/ases ; its crown is broad, with some slight 

 ridges, and with a single posterior and a pair of lateral imi)ressions. 

 The principal frontal bones are somewhat concave anteriorly to 

 receive the posterior intermaxillary j^rocesses ; the latter are very 

 long, flattened, and move below the tui'binal bones, which are much 

 developed, crescent-shaped, and meeting with their convexities on 

 the middle. The intermaxdlaries are flattened, with the lateral 

 branches well developed. The maxillaiy is strong, of moderate 

 length, and very irregularly shaped. The mandibula is low, of mo- 

 derate length, without an open slit between the articulary and den- 

 tary bones. Vomer broad and smooth, with the anterior margin 

 concave ; palatine stylifonn. The base of the skull is veiy broad, 

 flat, and smooth. Tympanic and opercidar bones as in Chorisochis- 

 mns ; structure of the humeral arch and of the pubic as in Choriso- 

 chismns and Sicyases. 



Both the abdominal and the caudal portions of the vertebral column 

 are composed of thirteen vertebra, the length of the former being to 

 that of the latter as 1 : 0-G6. There are no other essential differences 

 from the skeletons of the genera mentioned. 



lines. 



Length of the first vertebra 2-| 



Width of the first vertebra 4| 



Length of the second vertebra 2^ 



of the seventh vertebra 2^ 



of the fifteenth vertebra Ig 



of the twenty -fifth vertebra Ij 



of the abdominal portion 28| 



of the caudal portion 19 



