IN Semon's Zoologische Forschungsreisen, Lieferung xxii. (1904), Disselhorst treats of “Die maennlichen Geschlechtsorgane der monotremen und einiger Marsupialen.” On p. 123 are two text figures, both copied from Sir Everard Home, Phil. Trans., 1802, plate xii. One represents the male genital apparatus of Echidna hystrix, the other, Fig. 1B of the German work, the stretched male organ of the same animal. Now this Fig. B is, in Home's paper, correctly named “penis of the Drake.” Needless to say, this Drake's organ does not in the least agree with that of Echidna, as which it is described in the German work, and our author is sorely puzzled about some of the details, cf. p. 131. This may well be the case. Errors and blunders have been made ere now, but the serio-comic point is that this Drake figure has, in the process of reproduction, asumed mammalian characters. In the original figure the base is surrounded by well-drawn feathers, and such are mentioned in the explanation of the plate. The thing is also correctly copied by Owen in his article Aves in Todd's “Cyclopaedia,” further in the “Anatomy of Vertebrates,” vol. ii., Fig. 119, and Owen directs attention to an important error committed by Home in his interpretation of the urethra. But in the recent figure, wrongly attributed to Echidna, the feathers have lost their character as such, and have turned into hairy structures! Who has done this? The author or the artist, or have both combined to correct the faulty original? It is such a strikingly pretty figure that it is almost sure to be propagated, perhaps to be used as a proof of the affinity of the oviparous mammals. But a drake is a drake, for all that.