38 The American Geologist. Juiy, i89i 
division, but Herr Jiikcrs mode of dividing tliat excites our apprehen- 
sion. Instead of tlio customary gemmation we are introduced to a pro- 
cess of nomenclatural fission vvliicli we confess is new to us. Its chief 
cliaracteristic seems to consist in the entire dliappearancc of the original 
tjenus. We cannot but pronounce it a most flagrant violation of the 
rules of nomenclature. 
The genus Pristlonraptus (one of the two unnatural oflFspring which 
have thus devoured their parent) is characterized by an axis straiglit or 
bowed outward, a free mouth opening formed at the expense of the bev- 
elled upper lip; thecal processes when present are found upon the under 
lip. 
In Pomatograptus (gen. n.) on the contrary the axis is straight or 
curved inward, the mouth opening small under the over arching upper 
thecal lip. 
Herr Jakel closes his remarks upon classification by the following 
italicised paragraph : 
''This highly interesting case (the above ' parallel ^ } with many others 
shoivs that the one-rowed and more-rowed Oraptolites are not systematic- 
ally separable bntare to he classified phylo genetically and naturally from 
a higher point of view." 
The description of Retiolites which is perhaps the least faulty portion 
of Herr Jiikel's article terminates the section devoted to Graptolites. 
At the outset Herr Tornquist^ feels compelled to except to the author's 
statement. He says : Little if anything Is added to our knowledge of 
the generic structure beyond the points elucidated by the Swedish 
paleontologists during the previous decade. We need only mention the 
author's proposition to classify Retiolites geinitzianus along with Pristo- 
graptus (Monograptus). 
Herr Jiikel tells us (p. GGO) that after acquainting himself with spe- 
cial literature of the Graptolithen-Gestein he found it impossible to in- 
form himself with regard to the " almost numberless " species on record. 
AVliilc knowiiif^ little of the Monograptidae we detect some signs which tend 
to make us siisi)i(n<)ns of tlie new genera. Herr Jiikel believes that a classifica- 
tion based (priiiciiially at least) upon the cliaracters of the mouth opening could 
be applied with advantage to all graptolites, inchiding "tlic two and more 
rowed." (p. 666.) Again; "All the various types of Muni^raptids find parallel 
forms as well among the two-rowed as among the conipduiid forms." Rather 
unfortunately \vc tiiink, he continues; "A very remarkable example is furnished 
by Mii/Kfijniptiis <( .^7/s. i5arr. which with its alierrant peculiarities possesses its 
coriespondiiig parallel form in Didymof/raptus liinmrroixttiis Nicli., and Didymo- 
(jrojitii.f (jiiadriiiiiirrnnatiis Hall" (p. GG5). Further reading (p. 67G) shows this 
'■parallel " to roiisist in the possession by 3/. ^e.s^/.s' of /"'o spines on the inider lip. 
This peculiarity the autlinr i-egards as worthy of generic (fistinrtion. Provision- 
ally it is left under Fristiiji/nii'lna hut lie remarks tliat if the reuiaininggraptolites 
should be classified along the lines lie lays down this should form thetyjieofa 
new genus. AVe eonless to having little sympathy with such genera. 
iTornquist, Sv. L., 18t>0, Undersilkningar ilfv. Sil.iansoniradets Grapt., p. 7. 
"The very first lines relating to that genus [Retiolites]- 'Although the general 
structure of Rptnilites ycinitzianns liad already been quite correctly recognized 
and very aptly figured by Barrande and Sii.ss, it seems to me ' etc., seems rather 
incomprehensible, since it is known that Barrande and Siiss entertained entirely 
dit¥erent conceptions of the structure of that genus and how sharply the former 
protested against the latter's interpretation of its rhahdosoma. Tiie author seems 
to have taken no cognizance of what has been written in recent times on this- 
matter, for example, in as important a work as Tullberg's 'Skanes (iraptoliter.' " 
