2220 Journal of Applied Microscopy 



it brings about naturally in the field, unless it can be grown in quantities, and 

 inoculations be made by any person of ordinary intelligence and good common 

 sense. The grain field is not a place suited for the carrying on of experiments 

 in the culture and inoculation with fungi by the methods that can be employed 

 in a bacteriological laboratory. The experiments that have been carried on, not 

 only in the United States, but elsewhere in attempting to destroy chinch bugs 

 and grasshoppers by inoculating them with cultures of different fungi, have been 

 only partially successful. It has not been a difficult matter to grow the fungi in 

 sufficient quantity with which to make the inoculations, but the uncertainty of 

 atmospheric conditions suitable for the germination of the spores and the entrance 

 of the hyphae into the bodies of the insects inoculated has been the one serious 

 disadvantage over which there is no control. 



As yet I have not tried to inoculate either grasshoppers or caterpillars from 

 pure cultures of Empusa. I have only made a beginning in growing it artificially. 

 In all probability if it can be grown in quantity it will be of no more value in 

 exterminating insects than Sporotrichiim and the South African Mucor. But 

 while little may be expected from an economic standpoint, there is something to 

 be gained from a study of its cultural characters both morphologically and taxo- 

 nomically. So far as I am aware it has not been grown before in an artificial 

 culture medium ; if it has, I shall be duly grateful to anyone who will inform me 

 concerning the methods employed and with what success it was grown. 

 The University of Nebraska. JOHN L. SheLDON. 



A Method of Demonstrating Involuntary Muscle Fibres. 



The following method of demonstrating involuntary muscle fibres will some- 

 times be found convenient, and will give very fair results. The method will be 

 found especially useful in cases where the preparation is needed in a hurry, and 

 there is not time to wait for the fresh tissue to macerate. 



A celloidin section of some organ containing involuntary muscle, i. e., the 

 small intestine, is taken from the laboratory supply, and is stained deeply with 

 some double stain, i. e., haematoxylin and eosin. The section is then put into a flat 

 dish or watch-glass of absolute alcohol or synthol ; the celloidin is thus quickly 

 dissolved and the muscular layer (in the case of a cross section of the intestine, 

 the circular layer) may be easily separated from the other tissues, and, with sharp 

 teasing needles may be very finely teased. This teased material is then dropped 

 into a narrow bottle containing xylol or some other clearing fluid, the narrow 

 bottle being used so that the excess of clearing fluid may be easily removed and 

 the muscle fibres be thus transferred to a slide, with a minimum amount of clear- 

 ing fluid. A drop of balsam and a cover-glass complete the operation, and 

 though there will probably not be many fibres that are entirely separate from the 

 others, a very good idea of the size and shape of the fibres and their nuclei 

 may be obtained. Albert M. Reese. 



Syracuse University. 



