1913] Observations on Chcetotaxy of Calliphorinae. 259 



On July 29 the following were taken at meat near the 

 Bussey Institution, Forest Hills, Mass. 



L. sericata: 277 individuals— 3, 3, 3, 3. 1 d^ —3, 3, ab, 3. 



1 9 —5, 3, 3, 4. 1 9 —3, 2, 2, 4. 



4 9 9—3, 2, 2, 3. 2 9 9—3, 3, 2,3 . 



2 9 9—3, 3, 3, 4. 19 —3, 4, 3, 3. 

 1 9 —3, 3, 4, 3. 1 cf —3, 2, 3, 3. 



The frequent lack of anterior post-achrosticals either on one 

 or on both sides is interesting as it denotes approach toward 

 L. caesar. The general habitus, however, is typical sericata. 

 A single specimen of caesar taken in this lot was 3, ahc, ahc, 3. 

 Thus it appears that chaetotaxy alone cannot be relied upon to 

 determine the species with certainty. This will appear from 

 the following observations and even more clearly from the 

 breeding experiments. 



On Aug. 5, at meat at Bussey Institution, were taken: 



L. sericata: 311 indidivuals — 3, 3, 3, 3. 1 cf — 3, ac, 3, 3. 



1 c^— 3, 3, 2, 3. 1 9—3, 3, 2, 3. 



1 9—3, 3, ac, 3. 

 L. ccEsar: 1 9—3, 2, 2, 3. 



L. sylvarum: 1 9 — 3, 3, 3, 3, with two bristles on margin of second abdom- 

 inal segment (for brevity written 2 ab. br.) 



On Aug. 6, at meat at Bussey Institution, were taken: 



L. sericata: 68—3, 3, 3, 3. 1 0^-3, 2, 3, 3. 



On Aug. 8, at the garbage scow, Boston, were taken at meat: 



L. sericata: 955 individuals — 3, 3, 3, 3. 1 cf — 3, 3, ac, 3. 



1 cf —3, ac, 3, 3. 1 cf —3, 3, 2, 3. 



2 o'cf- 3, ab ! c, 3, 3. 19 —3, abc, 3. 3. 

 1 9 —3, 1, 2, 3. 19 —3, ac, ac, 3. 

 1" 9 —4, 3, 3, 4. 19 —3, 3, 4, 4. 



1 9 —3, 4, 3, 3. 19 —3, 2, 1, 3. 



5 9 9—3, ac, 3, 3. 2 9 9—3, a6c, 3, 3. 



3 9 9—3, 3, ac, 3. 3 9 9—3,3,2,3. 



4 9 9—3, 2, 3, 3. 



Flies having the habitus of cassar were as follows: 



5 cf 0^-3, 2, 2, 3. 9 9 9—3,2,2,3. 

 1 9 —3, abc, 2, 3. 



On Aug, 9 at a short distance from Bussey Institution on leaves near a pond the 

 following were taken: 

 L. sericata: 1 cf — 3, 3, 3, 3. 

 L. caesar: 1 9 —3, 2, 2, 3. 



L. sylvarum: 2 cf cf — 3, 3, 3, 3, with 2 ab. br. 



1 cf —3, 3, 2, 3, with 2 ab. br. 



4 9 9—3, 3, 3, 3, ab. br. lacking. 



On Aug. 10 at same place the following were taken at meat: 



L. sericata: 4 cf cf— 3, 3, 3, 3. 100 9 9—3, 3, 3, 3. 



2 9 9—3, 2, 2, 3. 2 9 9—3, a / be, 3, 3. 

 1 9 —3, (a), 3, 3, 3. 



L.ccesar: 3 cf cf— 3, 2, 2, 3. 20 9 9—3,2,2,3. 



L. sylvarum: 1 cf — 3, 3, 3, 3, with 2 ab. br. 

 1 9 —3, 3, 3, 3, with 2 ab. br. 

 An indeterminate cf Lucilia — 3, abc, abc, 3. 



