70 THE AMERICAN MONTHLY [May 



they shrink greatly so as to render mounting unfeasible. 



Small flat fish like soles and dabs, two inches long, 

 mount easily. Kill them in dilute alcohol, arrange on 

 the glass as soon as dead and while limp. Carefully lay 

 out the fins when they will dry and adhere well. Keep 

 the side near the glass flat. As few animals adhere to a 

 thin paper soaked in bees-wax, it can be laid over the 

 animal and pressure applied of a fairly uniform nature 

 upon thick and thin parts. This is best done by using a 

 weight upon a stout glass covered with several thick- 

 nesses of tine thin flannel. Regulated so as not to dis- 

 tort the animal but rather to retain the shape and show 

 the internal structures, the specimen will dry through the 

 flannel and keep flat on the glass. Specially high parts 

 can be pressed without flannel and with heavier weight. 



Marine worms, like Sabella, and others make most 

 excellent transparent slides, which show shape, color and 

 internal structure. Kill them by retaining a short time 

 in dilute alcohol and dry them before decomposition 

 injures the small blood-vessels. In Nereis, the chief 

 blood-vessels and tlie smallest branches may be shown 

 while the even blood keeps its red color for years. 



Priapulus. — This form can also be mounted without 

 staining. Kill in fresh water. When the body begins 

 to get limp arrange it neatly on the glass. It will 

 adhere without lateral contraction. If mounted at once 

 or after standing in alcohol, the body is too hard and 

 will not adhere while on drying it contracts laterally pro- 

 ducing distortion. To avoid this and to display the in- 

 ternal anatomy, cut the specimen open from end to end 

 and stain with Beale's carmine or Kleinberg's haema- 

 toxylin. This brings out the musclar structure of the 

 body-wall and the general internal anatomy. 



AreniCOLA. — Cut the animal open and displace the 

 intestine with appendages. Display them on the glass 

 along side of the body. This partial dissection will 



