April, '09] JOURNAL OF ECONOMIC ENTOMOLOGY 95 



Mr. Sanders: I use a double coated non-lialation plate. This 

 larva which I have photographed was in a shall oav glass dish with no 

 glass between it and the lens. 



A Member: What is your enlarging apparatus? 



Mr. Sanders: Any ordinary camera lens can be used. The bro- 

 mide paper is an exceedingly fast paper, faster than Velox, perhaps 

 a hundred times, but is printed and handled in the same way. 



Mr. Parrott: What paper do you use? 



Mr. Sanders: I have forgotten the name of the brand but any 

 bromide paper is satisfactory. 



Chairman Britton: The next paper on our program is ''Photo- 

 micrography of the Diaspina?." by ]\Ir. R. A. Cooley. 



An abstract of the paper was given at the meeting, the paper in 

 full follows : 



PHOTOMICROGRAPHY OF THE DIASPINAE 



By R. A. CooLEV. Bozeman, Montana. 



In these days when economic entomologists are frequently called 

 upon to make scattering identifications in widely differing groups, 

 it is desirable that systematic papers be written in unmistakable 

 language and that the illustrations be such as to leave as little doubt 

 as possible. The economic entomologist considers systematic work 

 to be a means to his end and believes that systematic papers should be 

 as generally usable as possible. The advantage of photographs over 

 drawings in illustrating entomological publications is well recog- 

 nized, though pen drawings of detail still and always will have a 

 place. 



Any one who has attempted to make pen drawings of the terminal 

 segments of the Diaspin^ is aware of the difficulty of securing any- 

 thing like a pictorial effect or even reliabty representing the original. 

 It has been found that good negatives can be made of these insects, 

 particularly when the microscopical mounts are made with this pur- 

 pose in mind. The following remarks, which are largely based on 

 our experience in preparing a series of photographs of the genus 

 Phenacaspis, wiU apply in many respects to the photomicrography 

 of other similar objects. 



Preparing the Mount.— The writer formerly employed glycerine 

 jelly as a mounting medium for scale insects on account of the greater 

 difference between the refracting qualities of the nearly transparent- 

 chitinous parts of the terminal segments and the glycerine jeUy than 

 exists between the ehitin and balsam. The glycerine jelly mounts 



