THE MONTHLY BULLETIN. 99 



thick coat of solid wax, which enal)k's them to withstand severe treat- 

 ment without bodily injury. In the subfamily Dactylopiince there are 

 several genera of insects which greatly resemble the mealy bugs, but 

 in this paper it is the aim of the writer to discuss only the genus 

 Pseudococcus, to which the true mealy bugs belong, and one species in 

 the genus Ceroputo, a very closely allied insect, which is included only 

 because it is so often confused with the true mealy bugs. 



GENERAL CHARACTERS. 



In the mealy bugs there are two distinct sexes, males and females. 

 Due to their minuteness (scarcely more than one eighth or one fourth 

 of an inch in length) the males are seldom observed. They have two 

 Avell-developed wings which enable them to fly and two long white anal 

 filaments (Fig, 21) which are characters common to nearly all of the 

 males of scale insects. The young males and females greatly resemble 

 each other, and while the male takes on a distinctly different form when 

 full grown, the female continues to look like the young, diifering only in 

 size and the covering which is later secreted over the body. When 

 mature the females are regularly oval, flattened and usually completely 

 covered with a fine white powdery wax whit-h extends along the sides 

 as lateral filaments, with often two or more at the posterior end (com- 

 monly called tails), which may or may not be longer than those along 

 the sides. The average length varies from al)0ut one fourth to three 

 eighths of an inch and the width from one half to two thirds the length. 

 All have six legs and are able to move about freely throughout their 

 entire existence. 



There are two distinct methods of reproduction: one where eggs are 

 laid and the other where the young are born alive. There is quite a 

 varied method, also, in the arrangement of eggs. In some cases they 

 are laid in loose cottony masses, in others the eggs are enclosed in a 

 tightly woven egg sac (ovisac), which does not include the female, 

 while in still others the eggs are enclosed in an egg sac Avhieh also 

 entirely envelops the female. These characters are mentioned because 

 they are exceedingly important in distinguishing the various species, 

 and it is the belief of the writer that we will never have an accurate and 

 scientific knowledge of all stages of the various species of mealy bugs 

 until more definite work is done on the life histories of all of these 

 species as they occur, not only upon their favorite host plants, but upon 

 many others which they infest, for no doubt their habits are somewhat 

 determined by the host plant. 



GENERAL LIFE HISTORY. 



As previously stated, some of the mealy bugs are born alive and 

 others emerge from eggs previously deposited by the females. In either 

 case the young usually appear about the same time which, roughly 

 speaking, covers a period from the first of October until about the first 

 of February or even later. In greenhouses and conservatories where 

 the insect lives imder artificial conditions, eggs and young may be found 

 almost any season and several broods appear, while out of doors there 



