Hg FESTSKRIFT FÖR LILLJEBORG 22 



In Spirilla reticulata Pelseneer found a "short junction of the two visceral 

 nerves" which he regarded as being produced in the same manner as in the OEgop- 

 sids and not by a long "commissure" as in Sepia. In the OEgopsids it is not how- 

 ever always a "short junction" of the visceral nerves. Posselt calls it "a broad" 

 commissure in Todarodes sagittatus; and of Vcranya's two commissures one is quite 

 long 1 , namely the posterior, which is homologous to that of other Decapods. In Chan- 

 uoteuthis there is no true commissure, but the nerves unite and separate again a 

 little further back-. The form of junction is, as we see from this, variable, and it 

 the commissure is long in Sepia and short in Spirilla some OEgopsids have a long 

 commissure, too, so that Spirilla is in this respect not more aberrant from the Scpui- 

 type than the OEgopsids. 



By the above I hope I have succeeded in removing the motives which com- 

 pelled Pelseneer to unite Spirilla with the OEgopsids and at the same time given 

 sufficient reasons for my own opinion that Spirilla is more closely related to the 

 nearest ancestors of the Sepia-Loligo group. I do not doubt that this opinion will be 

 strengthened by further anatomical investigation of new material but before con- 

 cluding these lines I want to call attention to some more facts that tell in the same 

 direction. The arrangement of the leaves of the nidamental glands in Spirilla is 

 exactly the same as in Sepia and Loligo, as can be plainly seen from Huxley's 3 

 and Pelseneer's 1 figures. The leaves are radially disposed at the posterior end of 



the gland or as Brock says "gehen — — — diese DrüsenbUlttchenreihen am 



Hinterende der Drüse bogenförmig in einander über". Brock regards this as char- 

 acteristic for the Myopsids as opposed to what he has found in the OEgopsids (Ony- 

 choteuthis and Ommatostrephes) in which "zwei DrüsenbUlttchenreihen — — rechts 

 und links von der Langsachse stehen" and as he adds — "vollständig von einander 

 getrennt" 6 . Another fact is that most OEgopsids (except Gonatus) have the brachial 

 cups disposed in only two rows, but in Spirilla there are more than two rows of 

 suckers on each arm. 



1 Cf. Appellöf Teuthol. Beiträge I p. 19 & fig. 22. Berg. Mus. Aarsber. 1SS9. 

 "Ehe dieselben (visceral nerves) noch die Harnsäcke erreicht haben, vereinigen sie sich und 

 bilden nur einen Nerven. Etwa in der Höhe der Ureteren — — — — trennen sie sich wieder und gehen 

 nun direkt zu den Kiemen." APPELLÖF 1. c. p. n, Bergen 1890. 



3 1. c. PL I figs 6 & 7, PL IV figs, i, 2 & 4. 



1 I. .. Fig. c. 



' Zeitschr. f. w. Zool. Bd. 36, p. 566. 



