Evelyn,

You may find the following resources helpful.

Yasutake,T.W., and J.H. Wales.  "Microscopic Anatomy of Salmonids:  An
Atlas." United States Dept. of the Interior, Fish and Wildlife Service, No.
150

"An Atlas of Fish Histology-Normal and Pathological Features"  1995.  ed.
Fumio Takashima and Takashi Hibiya. Kodansha Ltd.

Groman, D.B.  1982.  "Histology of the Striped Bass."  American Fisheries
Society.  Monograph Number 3.

Grizzle, J.M., and W.A. Rogers.  1976.  "Anatomy and Histology of the
Channel Catfish."  Auburn University Agricultural Experiment Station.

Good Luck!

**********************************************************************
Mandy L. Annis
Columbia Environmental Research Center
4200 New Haven RD  Columbia, MO  65201

Phone:(573)-441-2940
Fax:(573)-876-1896
e-mail:mandy_annis@usgs.gov