this group are termed in Britain, and like the majority of the larger Sphingidæ, they are extensively distributed, occurring in almost every quarter of the globe. M. tersa is a native both of North and South America, as well as of the West Indian Islands. It measures about three inches across the wings; the general colour greyish olive-brown; the anterior wings entirely of that hue, with a few delicate parallel lines of a lighter colour, running from the base somewhat obliquely to the tip; posterior wings black at the base, brown along the external margin, with a row of cream-coloured triangular spots between these two colours; fringe of the wings white. The head is flesh-coloured, and there is a stripe of the same running along each side of the thorax; the back of the latter clay colour, the sides yellowish-brown.
The caterpillar (Plate VI. fig. 1) is of a delicate green with numerous small longitudinal spots of reddish brown; prolegs yellow; on each segment, except the second and third, there is a yellow oval spot, marked with black above and below, placed on a lighter ground; and higher up a longitudinal white stripe, commencing at the fifth segment and running to the tail, and having a series of ocellated spots placed on it; there is likewise a large ocellated spot, of a more complex description, on the fourth segment, in line with the others; tail red. The pupa is yellowish-brown. The caterpillar feeds on what Abbot calls wild thyme, but which is a species of spermacoce (S. hyssopifolia). The author
