420 



Fig. 76. — Strainer 

 for eggs. (Section 

 removed.) 





Fig. 77. — Shell vial for 

 rearing clinical mag- 

 gots. 



Phylum Arthropoda 



wide mouth which supports a 25 cc. Gooch crucible. 

 In this is placed a circular piece of a thin grade 

 of bleached muslin. Before being cut into suitable 

 patches, the cloth is immersed in a hot 2% 

 solution of sodium hydroxide, washed and baked 

 to a light brown in the hot air sterilizer. This 

 treatment improves the condition of the cloth for 

 straining. The color aids in the estimation of the 

 hatch. A small crystallizing dish is inverted over 

 the crucible. 



Maggot-rearing Vials. Shell vials (Fig. 77) 

 4 cm. in diameter and 12 cm. high are used in 

 rearing maggots for clinical use. Vials slightly 

 larger than these may serve the purpose better. 

 A section of autoclaved lung about 1 cm. thick is 

 placed in each vial and 1.5% peptonized glucose 

 agar is added nearly to cover the meat. A glass 

 slide within the vial rests upon the meat. The 

 vials are then stoppered with a snugly fitting, 

 cheesecloth-covered cotton plug and autoclaved. 

 Simmons uses evaporated milk added to agar in 

 rearing surgical maggots. 



Strainer jor Maggots. A strainer used for trans- 

 ferring maggots aseptically from one receptacle to 

 another or for implantation in the wound consists 

 of a small wire tea strainer supported by a beaker. 

 Cheesecloth which has been treated with sodium 

 hydroxide, washed and baked, is cut and fitted into 

 the strainer. A crystallizing dish is inverted over 

 it and the whole is autoclaved just before use. 



Fly Cabinet. A cabinet (Fig. 78) providing 

 regulated temperature and humidity is useful in 

 rearing flies and maintaining good egg production 

 the year round. During the cooler months the 

 temperature is raised to approximately 2 6° C. 

 During the warmer months it is sometimes better 

 to remove the cabinet to a cool room in the base- 

 ment or elsewhere. 



Brood Larval Cabinet. When larvae for stock 

 flies are grown on unheated meat a cabinet pro- 

 viding a draft to outdoors is needed to remove 

 offensive odors. One similar to the fly cabinet 

 equipped with an exhaust fan is suitable. An 



