FAMILY SCOLYTIDAE 587 



Xyleborus mancus, Blandford. 



Reference. — Blandford, Trans. Rut. Soc. Loud. 428 (i8g8). 



Habitat. — Ceylon. 



Tree Attacked. — Cocoa-tree {Theobroiua cacao). 



Beetle.— $ Front of head convex, sub-opaque, rather closely and finely punctate, with a 



short shining elevated longitudinal line alwve the middle of the shining blackish epistoma ; 



eyes rather deeply emarginate. Sides of the prothorax nearly 



Description. straight behind the middle, with a black conspicuous patch of 



piliferous punctures near the base. Elytra darker apically, nearly 



black, the apical declivity not very opaque, not concave on either side, but gradually raised 



towards the suture, with a somewhat irregular surface, the rows of punctures somewhat 



wavy, the punctures rather large shallow subnitid impressions, the interstitial punctures not 



perceptible. Length, 3.3 mm. 



On a first study of diseased cocoa-trees in Ceylon, Mr. E. E. Green, 



Government Entomologist, forwarded to Mr. Blandford 



Life History. three species of Scolytidae and Platypodidae which 



he beHeved were responsible for the attack. The 



Scolytidae proved to be Xyleborus scniigranosus, Xyleborus fornicatus, and 



Xyleborus (Eccoptopterus) sexspinosus. At the same time Mr. Green stated 



that he was not satisfied that the beetles were the real source of the disease, 



as a fungus was also present. Subsequently Mr. Green sent two other 



Scolytidae who were really responsible for the damage done. These proved 



to be new to science, and were described by Mr. Blandford as Xyleborus 



mancus and Xyleborus discolor. 



On the subject of the damage done Mr. Green wrote : — 



" I am. of opinion that the beetles first sent were not primarily 

 responsible for the injury, and this opinion has been corroborated 

 by the discovery of a fungus in all the diseased specimens of bark 

 submitted to Kew. 



" I am now forwarding two more species of scolytid beetles that 

 are found in the younger branches of the cocoa-tree, which really 

 are injurious to the plant. The}- form their tunnels in what appears 

 to be healthy wood, and rapidly cause the death of the parts 

 attacked. A dark chocolate or purplish stain spreads through the 

 tissues of the wood surrounding the galleries of the insect." 



Xyleborus discolor, Blandford. 



Reference. — Blandford, Trans. Ent. Soc. Land. 429 {1898). 



Habitat. — Tista Division, Bengal (J. C. Carroll) ; Ceylon. 



Trees Attacked. — Nahor (Mesua ferrea) : Tista Division ; Cocoa-tree 

 {Theobroiua cacao). 



