Apkii. 29, 1904.] 



SCIENCE. 



703 



by its date (1665) and by tlie fact that all 

 except the first word really constitutes a sub- 

 title. The British Association committee 

 alludes to a title of recent date containing 

 ninety-one words. Mr. Wilder's precepts are 

 admirable, but the heading of this letter shows 

 how even his example may be bettered. A 

 certain leading society persists in prefixing 

 the useless ' on,' and forces an author to en- 

 title his paper ' On the Tears of the Crocodile ' 

 instead of ' Crocodile's Tears.' 



Clearness. — Modesty, Mr. Wilder would sug- 

 gest, made an author say, ' Some Contribu- 

 tions to our Knowledge of the Morphology 

 of the Guyascutidfe,' instead of ' Guyascutid 

 Morphology,' and that same modesty, pre- 

 sumably, forbade him to suppose that the 

 casual biologist might not know what a guyas- 

 cutid was, and made him keep to himself the 

 precise nature of his contributions. The 

 enormous number of generic names and their 

 synonyms often makes it impossible for a 

 reader to tell the subject of a paper from its 

 title. A specialist on echinoderms turned out 

 at night to hear a paper ' On the Structure of 

 Apiocysiis/ only to find that it was an alga 

 (if my memory serves) and not the Silurian 

 fossil of that name. When a paper was pub- 

 lished on the fluid of the body cavity in a 

 certain animal the whole stafl: of the largest 

 natural-history museum was unable to say 

 what kind of animal was meant. In such 

 cases the explanatory word may lengthen the 

 title, but it is fully worth the space. Mr. 

 Knowlton's examples of ambiguity are not so 

 bad as these, but bad enough. Even the best 

 of them is not really free from doubt; for 

 example, what would an American botanist 

 understand by ' The Flora of the Coal Meas- 

 ures. An Ecological Study ' ? This reminds 

 me that a geological bibliographer innocently 

 placed in his slip-catalogue the title of a work 

 on 'Anthracite Coal Communities.' He has 

 since learned that this too is an ' Ecological ' 

 study, neither geological, nor paleontologieal, 

 nor zoological, nor botanical. 



In fine, let the man of words, whether 

 modest or 'intoxicated with the exuberance 

 of his own verbosity,' remember that ' Brevity 

 is the soul of wit,' and let the epigrammatist 



make for himself no occasion to say, ' Brevis 

 esse laboro, obscurus fio.' P. A. B. 



IIAHGINAL AND RIDGE SCALES IN CEPHALASPIS 

 AND DREPANASPIS. 



In two or three of his recent articles on 

 Tremataspis, Dr. William Patten has affirmed 

 his belief, contrary to that of all other writers, 

 in the existence of ' numerous pairs of jointed 

 oar-like appendages ' in certain fossil ostra- 

 cophores. His latest paper, in the December 

 number of the American Naturalist* is note- 

 worthy for its development of the thesis pre- 

 viously advanced by him to the eilect that 

 Gephalaspis is provided with a 'fringe of 

 jointed and movable appendages (25-30 pairs) 

 along the ventral margin of the trunk.' 



Happily, the author does not postulate the 

 existence of imaginary organs, as was done in 

 the case of Tremataspis; but this time actual, 

 deiinite structures are pointed out, familiar 

 to every one as marginal scales, and these 

 receive the new name of ' fringing processes,' 

 and are interpreted as appendages. Regard- 

 ing these structures Dr. Patten states that 

 ' there is little doubt that they are the ante- 

 cedents of the lateral fold of vertebrates,' 

 although in another paragraph it is remarked 

 that ' whatever their significance may be, there 

 is apparently nothing known in true fishes 

 that is exactly comparable with them.' 



The present writer can not agree with his 

 esteemed friend that these marginal scales, 

 as they are commonly called, are not precisely 

 what their name implies, and fails to see any- 

 thing remarkable about them, either in form, 

 in attachment or in position. Dr. Patten is 

 quite right in observing that they are marked 

 with the same surface ornamentation as trunk 

 scales, nor do they differ from the latter 

 in any other respect except that their ex- 

 tremities are free. The identical structures, 

 if occurring in the median line above or 

 below, would be pronounced ridge scales; if 

 along the fin margins, they would pass for 

 fulcra; if along the angles of modern flat- 

 bottonipd fishes, for marginal or lateral scutes. 

 It may be, in fact, regarded as a general 



* ' On the Structure of the Pteraspidse and 

 Cephalaspidse,' pp. S27-86.5. 



