In the year 1819 the University of Edinburgh acquired by purchase a large zoological collection from M. Dufresne, of Paris, including a cabinet containing upwards of 12,000 specimens of insects. Some years later (in 1855), when the whole of the University collections were formally transferred to the Science and Art Department, the Dufresne cabinet became public property.

While consulting lately the volume by Godart devoted to the article “Papilio” in the famous Encyclopédie Méthodique, I was surprised to see a reference to the “Dufresne cabinet” in one of the descriptions of new species, and it immediately occurred to me that the specimen in our possession must be the actual “type” of the species, which discovery led me to search carefully through the whole of the volumes devoted to insects in this well-known work, with a view to finding as many types as possible. At the same time, I thought it possible that Olivier, who wrote his great Histoire Naturelle des Insectes—Coléoptères about the same time, might also mention some of Dufresne's specimens, and this I found to be as I had anticipated.

In a collection of Indian butterflies purchased by the Edinburgh Museum in the year 1890, I found a specimen of Hestina which is of some interest. After carefully examining it, and comparing it with a figure by Oberthür of a form which he regards as a melanic aberration of the well-known Hestina nama, Doubleday, I have come to the conclusion that our example is another and more melanic form of the same species. From Oberthür's figure, which he calls ab. melanina (Études d'Entomologie, xx., 1896, p. 30, pl. 10, no. 177), the present specimen differs in the fore wing, in the absence of the inner row of whitish spots, in the size and position of the upper spots in the outer series, and in the spot at the anal angle being nearer to the base of the wing. At the base of the cell there is a rich cream-coloured sub-triangular spot, instead of the slender greenish streak. There is no ferruginous border to the hind wing, and the whitish streaks are more elongated, and in the anal half of the wing only very faintly indicated.

I have to apologise for placing this communication before you in a somewhat incomplete form. My work has been much interrupted in the past, and it will again shortly be stopped for a considerable time. I have therefore decided to place before you the results so far as they are worked out.

The purpose of this paper is to discuss the conditions under which the C discriminant of a system of curves furnishes a curve which at every point of its length is touched by a curve of the system.

Among the specimens from the Yorkshire Coal Field which have been collected by Mr W. Hemingway, Barnsley, and submitted to me for examination at various times, are the remains of several cones which are referable to the genus Sigillariostrobus, Schimper.

Notwithstanding the great frequency of the genus Sigillaria in the Coal Measures, and especially in the Middle Coal Measures, examples of their fructification are very rare. This is the more remarkable, as specimens of Sigillaria, showing cone scars, though not common, are occasionally met with. Possibly, however, the apparent rarity of Sigillarian cones is due, in part, to our inability at present to distinguish them in all cases from cones generally placed under the name of Lepidostrobus, which latter genus there is every reason to believe comprises cones that belong to several genera of Lycopods.

The first part of this paper was communicated to the Society on June 1, 1896, and published in the Transactions (vol. xxxviii. part iii., No. 20, pp. 681–755), the data there discussed being mean values of the climatic elements for each day in the year.

In the present paper an attempt will be made to focus the results deduced from an examination and reduction of the various meteorological registers kept in Edinburgh from 1731 to 1736 and from 1764 to the present time, with special reference to secular and other weather changes.

The condensed results of a number of minor papers dealing with subjects which have, in many cases, formed part of the daily routine of observation during the last ten years have also been included. Attention may also be called to the list of remarkable atmospheric occurrences, such as phenomenal gales, snow-storms, auroras, etc., which is contained in the appendix. In presenting this paper my warm thanks must be expressed to Dr Buchan, from whom I received invaluable advice when points of difficulty arose in the reduction of the observations.

(1) It is well known that Cayley effected the transformation of

by introducing an intermediary set of variables

connected with each of the other sets by means of a linear substitution of a peculiar type. The substitutions in fact were

and

where the determinant of the first substitution is unit-axial and skew, and the determinant of the second substitution is got from the preceding determinant by changing rows into columns, and where, therefore, the number of arbitrary quantities introduced by the two substitutions is only ½n(n−1).

Since the Organ of Jacobson was first described in 1811, a large amount of study has been given to its structure, development, and morphology; and as a result of these investigations, we have now a very good idea of the distribution of the organ in the animal kingdom, of its relations in many typical forms, and of its minute anatomy in a few representative types. With the exception, however, of Seydel's work among the Amphibia, very little has been done to the study of the comparative anatomy of the organ, and it is hoped that the present contribution will assist towards a clearer understanding of its comparative anatomy in the Mammalia.