January, 1902] 



FSYCHE. 



297 



to be identical. The confusion seems 

 to have arisen from the extremely close 

 resemblance of the polygonal glands of 

 the derm in each of the species, and from 

 not properly studying the scales super- 

 ficially as in them are found characters 

 which are certainly specific. Further- 

 more it appears, and the more I read 

 the literature upon the species the more 

 I am convinced, that in most cases the 

 scales sent to the specialists were nigra 

 and not depressa as supposed by the 

 sender. The writer has had nigra sent 

 him for depressa and vice versa ; of course 



Dr. Howard and S. nigra from Mr. 

 Pergande. The destinctive character of 

 each species is as follows. 



5. nigra. ? Scale very dark brown, ap- 

 proaching black. The entire outer margin 

 carinate, distinctly so anteriorly and posteri- 

 orly, marginally not so pronounced. Tex- 

 ture very thick, shiny, smooth. Elongate 

 oval 4 mm. long, 3 broad, 2 high. 



5. depressa. ? Scale, deep red brown, not 

 at all blackish, somewhat shiny. General 

 outline oval, flat, much narrower in front 

 than behind. Surface rugose, pitted and the 

 margin distinctly ribbed ; about the center of 

 tlie dorsum posteriorly is a slight but distinct 



Saissetia nigra. 



Saissetia depressa. 



Markings of the derm. 



this was misidentification where proper 

 study was not made. Recently I received 

 nigra on Anona reticulata from Grenada, 

 W. I., and a species on Coleus at Barba- 

 does, W. I., marked new var., of nigra, 

 collected and kindly sent to me by Mr. H. 

 Maxwell Lefroy, the imperial entomolo- 

 gist; he Says the same variety is found 

 on wild Agave. The supposed variety is 

 clearly i'. depressa. I have also perfect ex- 

 amples of S. depressa, on wild '^Almond" 

 {Tei-minalia) from San Juan, Porto Rico, 

 collected by Mr. Busck, U. S. Dept. of 

 Agriculture, kindly sent to me through 



depression. Marginal carina nearly obsolete. 

 Texture of the scale decidedly thinner than 

 in S. nigra. Size 3 mm. long, 24 broad, i 

 high. As to the microscopical characters, 

 there are slight differences. The derm of 

 depressa is more transparent. The lines 

 forming the polygonal structure in depressa 

 are narrower more sharpened edges. In 

 nigra they seem to be thicker and flattened. 

 The antennae of each are similar and quite 

 difficult to measure correctly owing to the 

 markings of the skin. 



Saissetia hemisphaerica. 



Lecanium hemisphaericiim Targ.-Tozz. 

 1867. 



