TRANSLATIONS AND NOTICES 



GEOLOGia\L MEMOIRS. 



On Fossil Ants. By Prof. O. Heer. 



[Mittheilungen der Naturforschenclen Gesellschaft in Zurich. Heft ii. pp. 167-^ 



174, 1848.] 



The Ants are amongst the most numerous of tlie fossil insects both 

 at (Eningen* and Radoboj, and offer many points of interest to the 

 geologist. We especially refer to the following : — ■ 



1 . Nearly all the fossil Ants are winged, and either male or female ; 

 two specimens only of the neuters have as yet occurred to me, although 

 these latter without doubt constituted the majority in the ancient 

 world. The reason of this is very clear. The winged Ants only could 

 rise into the air, and so be driven into the water, where some of them 

 would perish and be covered up in the mud. 



But these fossil Ants clearly show that this covering up by the mud 

 must have been very sudden, and much more rapid than in our exist- 

 ing lakes and ponds. The wings of Ants are but very feebly attached 

 to the thorax ; they remain on only until pairing takes place, and then 

 fall off of themselves ; and indeed even before this they are very 

 easily separated. Now were the Ants to lie even a short time in the 

 water before they were imbedded, the wings would surely fall off. 



2. Among the fossil Ants many more females than males occur 

 both at (Eningen and Radoboj. I have altogether examined 2/9 

 specimens of fossil Ants, of which 208 are female, 69 male, and 2 

 neuter. From (Eningen there are 118 females and 40 males, and 

 from Radoboj 90 females and 29 males ; there being obviously at both 

 localities about three times more females than males. 



Among existing Ants an inverse proportion obtains ; for, accord- 

 ing to the researches made by Huber, there occur on an average three 

 times more males than females. Probably the same proportion also 

 existed in the extinct fauna ; but more females fell into the w^ater, 

 being feeble and unwieldy, and so perished in greater proportion than 

 the more active and lighter males. Hence also arises the suggestion 



* [See Description of the Freshwater deposits of (Eningen, and Observations on 

 their Fossil Fauna and Flora, by Sir R. I. Murchison, Trans. Geol. Soc. 2ud Ser. 

 vol. iii. Part 2. pp. 277-290, and Quart. Journ. Geol. Soc. vol. v. pp. 233-237.— 

 Ed.] 



VOL. VI. PART II. F 



