51 



A new Locality for G-ossyparia ulnii. — Mr. C. H. Rowe, of Maiden, Mass., has 

 sent us specimens of this interesting imported European hark-louse whicli he found 

 upon the underside of the limbs of an elm tree at Brighton, Mass. It will be 

 recollected that Mr. Howard treated this insect in Vol. ii, pp. 34 to 41, and that it 

 has been previously found in Boston, New York, and Washington. 



Dr. Hulst's Collection of Lepidoptera.— We learn from Dr. Geo. D. Hulst that 

 he has donated his collection of Lepidoptera to Rutgers College. The collection is 

 reported to be very rich in Catocala, as we know it to be in the Geometrina and 

 Pyralidina, two groux>s in which Dr. Hulst has more particularly worked and which 

 he retains for the present in Brooklyn. 



GENERAL NOTES. 



SUGAR-CANE PIN-BORER AND CANE DISEASE. 



We have Just received from Mr. J. M. Hart, f. l. s., of the Royal 

 Botauic Gardens of Trinidad, a stylograpliio circular on the sugar cane 

 disease and its relation to the Pin-borer, Xylehorus perforans Woll.,* 

 together with the following letter of transmittal. The circular is pub- 

 lished entire, as it is a matter concerning which we have had consider- 

 able to say of late in these pages. 



Royal Botanic Gardens, Trinidad, July 12, 1892. 



* ' " 1 have the honor to send you a few notes on our cane disease, which I 

 think perhaps will interest you. I was one of those on the original committee of 

 the agricultural board of Trinidad, who thought that the Xyleborus was altogether 

 to blame. Subsequent investigations under the microscope showed that the canes, 

 or most of them, were first subject to the attack of a microscopic fungus, and that 

 the attack of the beetle was subsequent to the attack of the fungus, until the num- 

 bers so increased that the insect had for very life's sake to feed upon the nearest 

 available food, ;. e., healthy canes. I am one of those persons who, from many years 

 of experience in the cultivation of plants, have come to the conclusion that plants in 

 a weak state, from whatever cause, are liable to the attacks of insects more than 

 those in a healthy state, and that it is the weakness of the plant that invites the 

 insect attack. Plants, it is true, may be attacked when healthy and rendered im- 

 healthy, but the chances are that if in robust health they are well able to fight their 

 insect enemies, and to survive their attack or rather outgrow them. Insect attacks, 

 I believe, often spread and become epidemic in character among healthy plants, after 

 they have been introduced and allowed to increase in abnormal numbers on unhealthy 

 plants 



Our canes here have suffered from an alternation of dry and wet years, and as a 

 matter of fact, our sugar-planters never dream of an alternation, but plant cane, 

 generation after generation without change of even the variety cultivated or of the 

 stock with other estates. For long years this has answered, but, though brought up 

 by manures to a state of apparent "vegetative A'igor," the canes are actually con- 

 stitutionally weak and liable to insect and fungus attack in unfavorable seasons. 

 The Xyleborus has appeared and is credited with the mischief, simply because the 

 first cause (fungus) was unsuspected and unknown and unseen. 



*In recent numbers (vol. iv, pp. 342 and 402) we published notes on what is prob- 

 ably the same insect, viz, X. pubesceiis Zimm. In our first note the species was, 

 through a clerical error, incorrectly referred to as " X. inceus Zimm." — Eds. 



