Maskell. — On Coccididae. 77 



Although I find a few minute characters in my specimens 

 of S. atriplicis which seem different from those of P. mashelli 

 (the comparison being made between prepared specimens of 

 both), yet on the whole I believe the two to be identical, and I 

 shall therefore abandon mine, both generically and specifically, 

 in favour of Mr. Olliff. The specimens which I first received 

 came from Wentworth, New South Wales, on Atriplex sp., 

 and were sent by Mr. French. There were about twenty adult 

 females in the first parcel, and nearly as many more in a 

 second. All of these were so much covered with cotton that 

 I could not decide upon attaching them to the genus Piilvi- 

 naria, in which the insect is usually exposed at one end of a 

 cottony ovisac. The only difference between Pulvinaria and 

 Signoretia lies in this arrangement of the cotton, and may be 

 paralleled perhaps by the distinction drawn between Eriococcus 

 and Gossyparia. Mr. Olliff, who received his specimens (more 

 numerous than mine) independently from the same locality 

 and on the same plant, attached them to the genus Pidvinaria, 

 and in his figures shows the insect exposed at the end of an 

 ovisac. The specimens also which he has sent to me are 

 quite clearly exposed, and are Pulvinaria. 



It will be seen from the description to be given presently of 

 Pulvinaria tecta that specimens of that insect are frequently 

 so covered with cotton as to be invisible, whilst others are 

 exposed. I have seen also sometimes, but not often, insects of 

 P. inmimerabilis, Eathvon, and P. betulce, Linn., almost, if not 

 quite, covered. 



As regards the difi"erences mentioned above between my 

 specimens and those of Mr. Olliff, I find them to be such as 

 the following : In mine the last female antennal joint is less 

 than the seventh, and the joints of the foot bear no hairs ; in 

 Mr. Olliff' s the last joint is longer than the seventh, and the 

 feet have a few hairs. For the males mine have the abdomen 

 shorter than the spike, and the tibia is much less than three 

 times as long as the tarsus ; while in Mr. Olliff's the abdomen 

 is longer than the spike, and the tibia is more than three 

 times the length of the tarsus. These microscopic differences 

 may be considered as indefinite. In my paper of 1890 

 (Trans., vol. xxiii., p. 32) I remarked that a student of Coccids 

 "must be prepared at any time to find distinct departures 

 from generic types, and to consider any character whatsoever 

 as elastic and variable." In view of the locality in which 

 both sets of specimens were collected, and of the identity of 

 the food-plant, I shall consider my species identical with 

 that of Mr. Olliff. 



A somewhat embarrassing point arises, however, as to 

 nomenclature. The paper in which I reported Signoretia 

 atriplicis was read in October, 1891, while Mr. Olliff's descrip- 



