Normal Butyl Alcohol Technic for Animal Tissues with Special Reference to Insects

N-butyl alcohol is substituted in dehydration for the higher ethyl alcohols. No special clearing is necessary as n-butyl is miscible with paraffin.

The greatest advantage of this method is the elimination of both hardening agents (the higher percentage ethyl alcohols and xylol or benzol). Another advantage is the great time toleration of the processes of dehydration and infiltration. For example, tissues have been kept without deleterious effects in n-butyl alcohol for a year before infiltration. Also, aphids which have been kept in a hot (58°C.) paraffin bath for as long as four weeks, have sectioned well. For small insects and vertebrate tissues about five days proved necessary to insure satisfactory infiltration.

N-butyl alcohol was found to give better results than many other technics in serial sectioning of lightly chitinized insects, and in the preparation of embryological and other vertebrate tissues. This technic has been used as a routine method by beginning students in animal microtechnic with better success than attended the usual methods.