632 AMERICAN ASSOCIATION ADVANCEMENT OF SCIENCE. 
the dorsal fin, while the hæmal spines of the 10th to 16th vertebra 
are in. close connection with the expanded interhzemal spines supporting 
the anal fin. The 16th vertebra gives off large neural and hemal 
spines, the former having five interneural spines anchylosed with it as 
in the adult, while the hæmal spine supports nine interhemal spines, 
the vertebral column, has been as often considered as an interspinous 
bone as a vertebra. In the young specimens this vertebra, though separ- 
ated from the column as in the adult, has in close connection with it two 
ien above and two below, probably indicating that this vertebra is in 
reality the consolidation of two vertebral bodies, the 17th and 18th, while 
central rays of the caudal fin, and they and the 17th, 18th, and 19th ver- 
tebre are only represented by the free or “ floating " 17th vertebra which 
lies in the chain of interspinous bones of the caudal. 'This is the only 
_ instance of a vertebra existing as distinctly separated from the vertebral 
column known to the author. 
A dissection of the soft parts of the young shows the same arrange- 
ment as in the adult; the large liver extending in two lobes and enclos- 
ing the stomach and portions of the intestine, and the long intestine with 
its five or six oda The arrangement of the bundles of muscles is the 
same as in the ad j 
On comparing er Legs with Molacanthus an entirely different 
structure is observed. First, the external form of Molacanthus differs 
while the reverse is the case in Orthagoriscus. There are many largely 
spines of the 4th to 17th vertebra, and those of the anal with the hemal 
spines of the 10th to 17th vertebre. The vertebral column in Molacanthus 
