From having many experiments in hand, I did not sow the seed obtained by crossing both forms of the primrose and cowslip with both forms of the oxlip, which I now regret; but I ascertained an interesting point, namely, the character of the offspring from oxlips growing in a state of nature near both primroses and cowslips. The oxlips were the same plants which, after their seeds had been collected, were transplanted and experimented on. From the seeds thus obtained eight plants were raised, which, when they flowered, might have been mistaken for pure primroses; but on close comparison the eye in the centre of the corolla was seen to be of a darker yellow, and the peduncles more elongated. As the season advanced, one of these plants threw up two naked scapes, 7 inches in height, which bore umbels of flowers of the same character as before. This fact led me to examine the other plants after they had flowered and were dug up; and I found that the flower-peduncles of all sprung from an extremely short common scape, of which no trace can be found in the pure primrose. Hence these plants are beautifully intermediate between the oxlip and the primrose, inclining rather towards the latter; and we may safely conclude that the parent oxlips had been fertilised by the surrounding primroses. From the various facts now given, there can be no doubt that the common oxlip is a hybrid between the cowslip (P. veris, Brit. Fl.) and the primrose (P. vulgaris, Brit. Fl.), as has been surmised by several botanists. It is probable that oxlips may be produced either from the cowslip or the primrose as the seed- bearer, but oftenest from the latter, as I judge from the nature of the stations in which oxlips are generally found (2/13. See also on this head Hardwicke’s ‘Science Gossip’ 1867 pages 114, 137.), and from the primrose when crossed by the cowslip being more fertile than, conversely, the cowslip by the primrose. The hybrids themselves are also rather more fertile when crossed with the primrose than with the cowslip. Whichever may be the seed-bearing plant, the cross is probably between different forms of the two species; for we have seen that legitimate hybrid unions are more fertile than illegitimate hybrid unions. Moreover a friend in Surrey found that 29 oxlips which grew in the neighbourhood of his house consisted of 13 long-styled and 16 short-styled plants; now, if the parent-plants had been illegitimately united, either the long- or short-styled form would have greatly preponderated, as we shall hereafter see good reason to believe. The case of the oxlip is interesting; for hardly any other instance is known of a hybrid spontaneously arising in such large numbers over so wide an extent of country. The common oxlip (not the P. elatior of Jacq.) is found almost everywhere throughout England, where both cowslips and primroses grow. In some districts, as I have seen near Hartfield in Sussex and in parts of Surrey,