OF WASHINGTON. 67 



the cup-like coverings of Psyllidae found on the leaves of certain 

 Eucalypti." In this remarkable and often quoted paper, which 

 still remains the most important contribution to our knowledge 

 of this subject, Mr. Dobson proves that the Lerp objects are the 

 cases spun by the larvae of certain Psyllids. Three different 

 forms of Lerp are described by him, two of the imago Psyllids 

 figured but only one described and named Psylla eucalypti; the 

 third Psyllid is only briefly mentioned. 



In 1879, Dr. V. Signoret (Ann. Soc. Ent. France, Bulletin, 

 p. LXXXV) proposed the new genus Spondyliaspis of the 

 family Aleyrodidas, founded solely upon what Signoret considered 

 as the scale of the insect. He had seen only dried-up specimens 

 of larvae or pupae found beneath these scales, and from the fact 

 that they showed four wing-pads correctly concluded that the 

 insects could not belong to the Coccidae. The scales are 

 described as being of the form of a conical shell (coquille) with 

 a number of external ridges which are either spinous or smooth. 

 The three species described by him (S. spinosulus, cereus, and 

 bancrofti} are distinguished by the color of the shell and the 

 number and nature of the ridges. 



In 1 88 1 (1. c., Bulletin, p. CLVIII) Signoret returns to this 

 subject and states that his genus Spondyliaspis was identical with 

 Maskell's genus Inglisia, described as a Coccid. 



In 1883 Mr. J. G. Otto Tepper (Journ. Linn. Soc., 17, No. 

 99, p. 109) published some "Remarks on the Manna or Lerp 

 Insect of South Australia" in which he confirms Mr. Dobson' s 

 discovery regarding the origin of lerp. 



In 1891 (Internal. Journ. Microscopy, 3rd series, vol. I, No 3, 

 p. 87) appeared, without indication as to the author, a figure of 

 a specimen of lerp which is apparently identical with one of the 

 lerps figured by Dobson ; the few lines of text accompanying 

 this figure do not convey new information. 



According to the minutes of the Proceedings of Linn. Soc. 

 New South Wales (2), vol. IX, November 28, 1894, Mr. A. Sid 

 ney Olliff exhibited a Psylla from West Australia "which makes 

 elongate semi-transparent, horny larval coverings on the foliage 

 of Eucalyptus rudis. In structure and habits it is closely 

 related to Psylla eucalypti, and it is proposed by Mr. Olliff to 

 call it Psylla periculosa" No description of this species has 

 ever been published. 



Finally, in 1896, Mr. W. M. Maskell in his Monograph of the 

 Aleurodidae (Trans. New Zealand Institute, vol. 38, p. 411) 

 vigorously "objects to Signoret's interpretation of his genus 

 Inglisia which is a true Coccid, and adds that from specimens 

 received from Signoret himself there was no doubt that the genus 



