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Show 1897.] BUTTERFLIES OF THE GENUS TERACOLUS. 19 describes thus:-"below all four wings are white, with black marginal spots and the costa of hind wings orange at base." Mr. Trimen contends that as T. speciosa has the hind wings yellow below, it cannot be this species ; but I have seen not a few specimens in which the yellow is reduced to but the faintest tinge, and which would thus very well suit the description ; moreover the hind-marginal spots are a normal feature in T. speciosa, but whenever they occur in T. jalone, which is very seldom, they are always accompanied by strong black neuration and a distinct blackish discal ray from costa, to which striking features no reference is made by Godart. But Mr. Trimen's chief contention is that at the time when Godart described his insect there were no Europeans in Natal, which is the only locality where T. speciosa has been found at the present day. Godart gives no locality for his specimen ; but this argument does not seem sufficiently cogent to induce m e to apply his name to a species which clearly does not agree with his description, when we know of another species which suits it reasonably well \ T. ione, as here restricted, is a very local insect, being only known at present from the coast-belt of Natal, and is replaced a short distance inland by the wide-ranging and variable T.phleggas, Butl. ( = jalone, Butl.). T.jobina, Butl., is the dry-season form of T. ione. 1 [The point here discussed cannot now be settled ; only probabilities can be weighed, in conjunction with the comparison of an incomplete description with the known varieties of the two nearly related forms in question. Perhaps I may here quote what I published in 1889 (S. Afr. Butt. iii. p. 103):-" It is not practicable to determine with certainty the exact form of male upon which Godart (loc. cit.) founded his Pieris ione, his description being too brief and no locality being given; but as be describes the underside as white, and as it is improbable that he should have had before him in the year 1818 any of the more locally restricted Southern forms, I consider it judicious to regard as the typical T. ione the form [ione of Reiche and of Hopffer, jalone of Butler, & c ] I have above described, which has a very wide Tropical African range, extending northward to the White Nile on the east and to Senegal on the west." As regards Godart's description of the underside of the hind wings, it should be observed that his words are " avec des points marginaux noiratres^ which means that those markings are very small and blackish-not that they are " black spots " as translated by Mr. Marshall. This is clear from Godart's describing, just before, the corresponding larger markings on the upperside of the hind wings as "une suite de taches noires" It would thus appear that in Godart's insect the underside marginal marks were mere blackish dots, and it is reasonable to suppose that the other blackish features-the discal ray and the neuration-were correspondingly reduced. I may note that in the Mozambique male figured by Hopffer (Peters' Eeise Mossamb. t. xxi. figs. 1 & 2), although the discal ray is reduced to some very faint brownish traces and the black neuration is extremely fine, there are yet three diffuse blackish spots on the nervules along the upper half of the bind margin. As a fact, all the markings in question are highly variable; and it is not more remarkable that Godart should have omitted to mention the discal ray and neuration if he had a faintly-marked example before him, than it is-supposing, on the other hand, that his type was the Natalian form T. speciosus-that he fails to note the costal commencement of the discal ray, which in that form is always well-marked and the most conspicuous marking on the underside. Godart gives no locality for his Pieris ione; but Boisduval-who states (Sp6c. Gen , Pref. p. ix, 1836) that he had been able to verify a number of Godart's 2* |