ANIMAL INSTINCT.
[To THE Exams Os THIN •seacrarea."] Sin,—In your article on "Dogs and Bicycles," in the Spectator of October 17th, there occur two passages from which I would respectfully dissent. In speaking of the acquired power of birds to avoid fast trains and telegraph-wires, as I understand the paragraph, you say that this acquired know- ledge is "probably transmitted now from generation to geueration." I somewhere recollect to have ny.t with a parallel passage in one of Darwin's works. Again, in the same paragraph, you say that "Instances in which they [the birds] are killed by a passing engine are very rare." With regard to the latter I may say that last week I received a partridge that had been so killed, and from careful inquiry of the platelayers I find that the phenomenon is not by them regarded as rare. In respect to the former passage I ground my objection on personal observation and on the circumstance that materials for forming a judgment are not forthcoming. My personal experience, which militates against the proba- bility of this acquired knowledge being transmitted from generation to generation, is as follows :—Attached to my house are two telegraph-wires, and as they are in contiguity to my bedroom I have ample opportunity during the morning hours to record any collisions by birds that may occur. I must also explain that the ridge of a long building running parallel at about the same height, and at a distance of about twelve feet from these wires, renders them more trap-like than they would be in the open country.
When the wires were first put up, twenty-two years ago, was surprised at the quantity of birds that struck against them during the summer mornings, and thought that after a lapse of time there would be an abatement of the collisions. This is not the case, nor can I see that there is an appreciable difference at the present time. My cat quietly takes up her post in the morning as did her mother for several years, and often gets rewarded. Many species of birds fall victims, generally of the smaller sort, although last month I had a partridge. As the observations include only those made when the sun was above the horizon, the night-flyers are excluded. As by far the larger proportion of the collisions occur during the morning hours in the summertime, I have thought that it is probably due to the birds' attention being pre-engaged daring nesting-time,, the early morning in that case, I believe, being always devoted to the rather severe labour which maternity involves. I cannot gather either from this or from other observations that anything like acquired powers are easily transmitted. I have on record cases where faculties are acquired, as is shown by an occasional failure when surround- ing circumstances have somewhat varied, and I believe the acquired faculties to be much more extensive than is generally supposed. Very many that were formerly classed as instine- tive—such, for instance as is displayed in a cleverly wrought nest—can oftentimes be shown to have been acquired.—I am, Sir, &c.,
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