662 ANATOMY OF THE MUZZLE OF ORNITHORHYXCIIUS, 



expressed sympathy, we cannot but feel that his critical instincts 

 have led him to castigate with undue severity our well meant 

 attempt after perfect fidelity of illustration. "We feel that he 

 has applied to photomicrographic illustrations criteria of clearness 

 and definition only applicable to the product of the draughtsman's 

 art. He must surely be aware that, at least in a high-power 

 photograph of a histological subject (as distinct from the test- 

 object of the professed photomicrographist), it is inevitable that 

 while a few points may be rendered definite, much is necessarily 

 out of focus and " smudgy." And even in view of his criticism 

 we must maintain that there are important points brought out 

 definitely and unmistakably in at least some of the " smudges " 

 which inspire Mr. Poulton with horror. We would instance the 

 lenticular bodies in fig. 10, the Pacinian-like bodies and their 

 relations in figs. 8 and 9, the abrupt ending of the medullary 

 sheaths of the nerve fibres in the base of the rod shown in fig. 11, 

 the peripheral and axial groups of filaments seen in transverse 

 section in fig. 13 (to which Mr. Poulton himself appeals further 

 on for our discomfiture), and very specially the isolated filaments 

 of the rod-organ shown in fig. 12. The latter figure is "smudgy" 

 enough in all conscience, and yet the positive evidence, free from 

 all shadow of doubt or deception, which such a photograph affords 

 of the independence and even of structural features of the fibrils 

 in question is perhaps sufficiently valuable to justify the exhibition 

 of even that highly inartistic and blotchy reproduction. 



Certain of the figures we are willing enough to consign to 

 oblivion, but even did the series stand alone in all the ugliness of 

 their imperfect reproduction, it would in our opinion be grossly 

 unfair to pass upon them Mr. Poulton's sentence of wholesale 

 condemnation. But it is to be noted that the photomici-ographs 

 do not, and were never meant to, stand alone, bu^ in connection 

 with drawings, both from natui-e and semidiagrammatic, which 

 had the express purpose of elucidating and interpreting the 

 obscurity of the photographs. With these drawings, we still 

 believe that to the unbiassed mind the unfortunate photomicro- 

 graphs may serve to convey an idea of certain of the appearances 



