726 
EDWARD W. SHAXN. 
Pseudoscarus guacamaia. J. &E. 
617. 
Clisetodontidae . ChBetodipterus faber. J. & E. 619, 
small. 
Obsetodon nigrirostris. J. & E. 
620, doubtful. 
(2) Personal Observations. 
Having’ noted the above-mentioned list of fishes in which 
the accessory scale is figured^ I next proceeded to examine 
the actual nature of such a scale in various specimens of fish 
in the collection at Giessen. 
Tlie scale was first examined in fishes most nearly allied to 
the salmon, and the following observations were made : 
(1) In all the species of Sal mo the accessory scale is 
encased in an adipose lobe, and is connected at its base by a 
splint of bone with the outermost fin-ray of the pelvic fin. 
(2) In other genera of the SalmonidEe^ the accessory scale 
is well developed, but it is not enclosed in connective tissue. 
(3) In other Malacopterygian fishes, especially in those 
which are adapted for active swimming, there is usually a 
marked accessory scale. 
In Clupea harengus this scale is very elongated, more- 
over it is subtended along its inner margin by a strip of skin, 
so that it forms a hollow conical outgrowth from the body ; 
there is no bony connection with the fin-rays. In Hyodon 
sp. (?) there is an elongated hollow scale, as in Clupea, but 
no trace of connective tissue. 
Passing next to the Ostariophysi, various Cyprinids were 
eligible for examination. A well-marked accessory scale was 
found in Abramis blicca, A. vimba, Squalius cephalus, 
Cyprinus (Leuciscus) dolula, Luciscus rutilus, and 
Chondrostoma nasus; but in Barbus vulgaris, though 
distinct, it is very small. 
* Except in Osmerus, and probably also in Tbaleicbtbys, 
Mallotus and Hy pomes us, but I have not bad an opportunity to 
examine actual specimens of tbe last-named genera. 
