et ordinem redigendis. Accesserunt singularia: de I. Dentibus Balaenarum et 

 Elephantinis. II. Lapide Manati et Tiburonis. [Motto]. Cum figuris. 

 Gedani, Litteris Schreiberianis. 1741. [4to., 3 p. 1., 38 pp., 1 1., 6 tab.] 



[3.] Jacobi Theodori Klein Historiae Piscium Naturalis promovendse mislTus~ter- 

 tius de Piscibus per branchias occultas spirantibus ad justum numerum et 

 ordinem redigendis. Cura observationibus circa partes genitales Rajse maris, 

 et ovarium Galei. [Motto]. Cum figuris. Gedani, Litteris Schreiberianis. 

 1742. [4to., 2 p. 1., 48 pp., 7 tab.] 



[4.] Jacobi Theodori Klein Historise Piscinm Naturalis promovendse missus 

 qvartus de piscibus per branchias apertas spirantibus ad justum numerum et 

 ordinem redigendis. Horum series prima cum additamento ad missum tertium. 

 [Motto]. Cum figuris. Lipsiae ; prostat apud Jo. Frid. Gleditschiutn ubi & reliqva 

 autoris opuscula. Gedani, Typis Schreiberianis. 1744. [4to., 3p. 1., 68 pp. ,15 tab.] 



[5.] Jacobi Theodori Klein Historiae Piscium Naturalis promovendae missus 



quintus et ultimus de piscibus per branchias apertas spirantibus. Horum series 

 secunda cum additionibus ad missus II, III, IV, et Epistola: de cornu piscis 

 carinae navis impacto. [Motto]. Cum figuris. Gedani, Litteris Schreiberianis. 

 1749. [4to., 2 p. 1., 102 pp., 1 1., 20 tab.] 



A remarkable work. It perhaps surpasses all other ichthyological publications in 

 incongruities between the definitions of groups and the contents thereof, and it is dif- 

 ficult to conceive how some could have originated. The definitions themselves are 

 sufficiently clear, and their practical application to forms would not appear to be dif- 

 ficult: the author however seems to have practically ignored his definitions of groups 

 when once framed, and to have proceeded, as some more modern naturalists have 

 done, by successive approximations of other forms to the types of his definitions, and 

 without checking the results by subsequent comparison with the latter. Judging 

 from the character of his various works, his analytical powers appear to have been 

 tolerably fair, but those of synthesis very defective ; this defect, an overwhelming 

 exclusiveness of attention to the special subject or idea for the moment under con- 

 sideration, and a neglect to verify the results afterwards by comparison of all the 

 elements, vitiated his entire work: in addition, he appears to have labored under the 

 disadvantage of an extremely limited autoptical acquaintance with natural objects, a 

 certain stolidity and inaptitude for applying even that little knowledge to the inter- 

 pretation of figures and descriptions,* and an unbounded trust in the reliability and 

 knowledge of others except Linne". The stolidity was not sufficiently diluted, with 

 unintelligible rhetoric to be entitled profundity. 



His classification is a strange one. In the first place, he distributes the fishes (in- 

 cluding therewith the cetaceans) into primary groups distinguished (I) by lungs 

 (Cete), or (II) by gills (a) concealed or (6) apparent from the exterior. The true 

 fishes with concealed gills were then arranged according to the (1) position (lateral or 

 inferior) of the branchial apertures, and (2) the larger sub-division by the presence or 

 absence of (lateral) fins, and finally (3) by the number of branchial apertures. The 

 fishes with externally visible gills were distributed into general groups distinguished 

 by positive characters, and the remaining left in one marked by negative characters, 

 that is, into groups "notable" for some character or other (as to (1), general form; 

 (2), snout ; (3), eyes ; (4), armature ; (5), breast or head ; (6), volubility of body), 



* For example, he often failed to consider that in symmetrical fishes the lateral fins were doable, 

 or present on both sides. 



