April 24, 1884] 



NATURE 



599 



reprinted, if not annually, at least at short intervals of 

 years, as furnishing one of the most valuable contributions 

 to economic geology. H. B. 



THE LA TE DR. ENGELMANN 



00 many years have elapsed since Dr. Engel- 

 *~^ mann, whose death was recently announced in jour 

 columns, wrote his academic dissertation " De Aatholysi 

 Prodromu?, 1832," that it is no matter for surprise if 

 many among the younger generation of botanists have 

 forgotten this little treatise, or have failed to associate its 

 author with the historian of American conifers and other 

 selected orders. This is the less surprising as, although 

 in Dr. Engelmann's systematic memoirs there are fre- 

 quent traces of his early morphological studies and of the 

 interest he felt in them, he, so far as I know, wrote no 

 treatise specially devoted to teratology other than the one 

 already mentioned. A few words on this little book may 

 therefore not be unacceptable to those who honour 

 Engelmann's memory. It would be an interesting and 

 not an unprofitable task to trace out the connection 

 between teratology and the modern views of evolution, 

 which is much closer than is generally imagined, albeit 

 the ideas oi^ natural selection and survival of the fittest 

 find no place in the older teratological literature. For 

 such a task I have neither the requisite ability nor the 

 necessary leisure. My object in alluding to the matter is 

 to call to mind the light in which Engelmann considered 

 the subject, influenced as he was by the writings of his 

 great fellow-countryman Goethe, whose views, originally 

 published in 1790, were by no means universally accepted, 

 even in 1832. Schimper and Alexander Braun were 

 among those who appreciated the value of Goethe's 

 theory, and those two learned men and acute morpho- 

 logists were Engelmann's teachers, and as we learn Irom 

 himself, exerted great sway over him. 



It is curious to contrast the modest pamphlet " De 

 Antholysi Prodromus," written in Latin, which I at least 

 do not find very easy to construe, with the more elaborate 

 " El^mens de Teratologic Vdgctale '' of Moquin-Tandon, 

 published nearly ten years later (1841). Moquin's work 

 is written in a style which even a foreigner can read with 

 pleasure. Its method, too, is clear and symmetrical, 

 but when we compare the two works from a philosophical 

 point of view, and consider that the one was a mere col- 

 lege essay, while the other was the work of a professed 

 botanist, we must admit that Engelmann's treatise, so far 

 as it goes, affords evidence of deeper insight into the nature 

 and causes of the deviations from the ordinary conforma- 

 tion of plants than does that of Moquin. .\ few illustra- 

 tions will suffice to make this clear. Speaking of pro- 

 gressive development, or as he calls it " evolitliom's 

 progressiis" Engelmann says that while it is only 

 obscurely indicated in celestial bodies, and with difficulty 

 studied in animals, " clarissiiiie apparct in plantis.'' 

 Plant-history is for Engelmann the narrative of the pro- 

 gress of evolution — " evoli/ti'o progrciiiois''' — and varia- 

 tions from the ordinary course are to be accounted for, 

 " ex niiiiio iiio/it, ft f.v nimio iiiipcdt/huh'," or, as we 

 should now say, from excess or from arrest of develop- 

 ment. 



The main end of a plant is to produce seed, and 

 the morphology of the plant appears to have been 

 considered by Engelmann as the result of a compromise 

 between this tendency [m'ius) and the progressive deve- 

 lopment of each individual part. The morphological unit 

 for him, as for Goethe, from whom he derived the notion, 

 was the leaf—" unitas autein in. foliis posita est " — and the 

 variations from the leaf-type were, as we have seen, attri- 

 buted to arrest of development, to reversion (irgyesius), 

 or to progression. But these changes were looked upon 

 then chiefly in relation to the greater or less development 



and specialisation of individual parts with little or no refer- 

 ence to their possible genealogical significance as elements 

 in a general pedigree of plants, or at any rate as suggestive 

 of such elements. Hereditary influence, however, was 

 not wholly overlooked ; on the contrary, Engelmann speaks 

 of it as " magni inonunti," and goes on to show how woody 

 plants frequently show, year after year, the same malfor- 

 mations, how perennial plants less frequently do so, and 

 how such repetition is much less frequently observable in 

 annuals and plants propagated wholly by seed. Only 

 " antliolyses epiphytica hei-editarice esse possunt " (§ 69), 

 says our author, by which he means that partial changes 

 are not perpetuated by descent, but only those in 

 which "omnes pliiriinive fores morbosi si/7it." It is 

 not necessary to stop to consider what amount of truth 

 there is in this assertion, but it is interesting to see the 

 use then made of the word "epiphyte." Engelmann, 

 influenced by his medical studies, spoke of "local," 

 "epiphytical," "sporadic," " enchoric," and "enchronic" 

 affections; enchoric changes being limited to certain 

 localities, enchronic alterations occurring at definite 

 tirnes. These terms have not been generally adopted, 

 while the signification now attached to the word "epi- 

 phyte '' is widely different from that which Engelmann 

 intended. He, at least, had not the right of priority in 

 this matter, for Bischoff, in his " Botanische Termino- 

 logie' (1S30), speaks of epiphytes as external parasites 

 (citing as examples Cusciita and Viscuin), in contradis- 

 tinction to entophytes. It would seem from this that in 

 matters of terminology custom overrides priority. But 

 this by the way. Our present concern is with the fact that 

 certain changes, or certain degrees of change, are more 

 likely to be perpetuated than others. Similarly we find 

 Engelmann calling attention to certain "critical" regions 

 of the plant,— spots, that is, more subject than others to 

 teratological change,— the apex of the stem in definite 

 inflorescences for instance (§67), a point subsequently 

 dwelt on by Darwin at some length, though he does not 

 seem to have been aware of what Engelmann had pre- 

 viously written on the subject. 



Lastly, reference may be made to the assertion made 

 by Engelmann that plants of a high state of relative 

 structural perfection '' struct tad magis evolutd et typo 

 nuigis coinposito," are specially liable to retrograde 

 metamorphis. This is a statement that from the nature 

 of things seems so reasonable that it is generally accepted 

 without question. Nevertheless, it is one which requires 

 qualification and further investigation. To take one case 

 wdiich occurs at the moment. Let any observer call to 

 mind the number of instances in which he has seen the 

 carpels the subjects of retrograde metamorphosis, and he 

 will probably find that such changes are far more common 

 in cases where the carpels are free and superior, than in 

 those in which they are in union one with another and 

 with the thalamus, as in the so-called inferior ovaries, 

 which are considered to represent a higher type of struc- 

 ture than do the free carpels. 



But the object of this note is not to discuss any parti- 

 cular view that Engelmann may have held, but merely to 

 call attention to his claims as a morphologist, claims 

 which are overlooked by reason of his greater — numeri- 

 cally greater — claims as a systematise 



Maxwell T. Masters 



SIWALIK CARNIVORA ' 

 T) Y the publication of the present memoir on the Siwalik 

 -D and Narbada Carnivora, Mr. Lydekker completes 

 the second volume of the series of the " Palseontologia 

 Indica" devoted to the Indian Tertiary and Post-Tertiary 



' " P.iIa=ontnlogia Indica," Series x. Indian Tertiary and Post-Terliarv 

 Vertebrala. V.l. ii. Part 6. Siwal.k and Narbada Carnivora. By R'. 

 Lydekker, 3. A., F.G.S.. K.Z.S. Published by order of His Excellency the 

 " leralof India in Council. (Calcutta, 1884.) 



