ABSTRACTS. 63 



lieart-sliaped cell begins to divide at its broadest end, and the two 

 Desniids which ultimately result are so arranged that conjugation 

 would he a natural sequel. 



I am indebted to Dr. O. Borge, of Stockholm, for very kindly 

 identifying the specimen for me, and a beautiful little sketch of 

 it which he was good enough to draw. 



EXPLANATION OF TLATE 1. 



Si a lira strum Dkkiei var. parallel um, Nordst. 



Figs. 1. & 2. Early stages of conjugation. Fig. 1. vertical view ; Fig. 2, front 



vievf. 

 Fig. 3. Conjugation complete, with the early stage of the zygo.spore. 

 4. The unusual formation of a conjugation tube, 

 f). The mature zygos]iore, showing the contents divided into four (the 



fourth being concealed by the other three), 

 (i. A zygospore with the contents divided into two parts. 



7. The contents of the spore contracted and escaping. 



8. Tl)e esca)ied contents of the zygospore, showing four embryonic 



Desmids (three vertical view, one front view) surrounded by the 

 periplasm. 



9. Four Desmids (two vertical view, two front view) with their sur- 



rounding periplasm. 

 ^ 10. Tln-ee Desmids (one of them a four-rayed form) produced in the 

 escaped contents of a zygospore. 

 11. The usual arrangement of three Desmids in tlie escaped contents 

 (vertical view). 

 Figs. 12 & 13. Two Desmids (fig. 13 with an atrophied nucleus) produced from 

 a zygospore. The arrangement shown in these two figures is most 

 frequently met with. 

 Fig.'14. An embryonic four-rayed form with its surrounding protoplasui. 



15. A Desmid (vertical view), .showing a four-rayed end ai.d a three-rayed 

 end in the same individual. 



Tlie Desmids are 26 /x to 28 f* in length, and are of the same diameter. Tlie 

 zygospores are o.'i /i to 38 ju in diameter, without tlie spines, wiiieh are S fx to 

 lU/i in lengtii, making a total diameter of .'lO /i to bb fi. 



Faria iiifernalis, Linnaeus. 



By Sir Arthur E. Shipley, G.B.E., F.R.S., F.L.S. 



[Read 15th June, 1922.] 



In the classical tenth edition of his ' Systema Natuiw,' that of 

 1758, Linnteus gives on page 644 the following list of genera 

 of his Group Intestixa : Oordius with three species, Faria 

 witli one species, Lumbricns with two species, Ascaris with 

 two species, Fa^ciola with two species, Hirudo with eight s|)ecies, 

 MijA'me with one sjjecies, Teredo with two species. 



Mijccine, the cyclostoni.e fish, and Teredo, the boring mollusc, 

 obviously had nothing to do with the Intestina. 



Altogether his characterisation of the species enumerated above 

 occupies only four and a half pages. 



The history of Furia is a curious one. Dr. Daydon Jackson 

 records in his interesting article on Linnaeus in the ' Encyclopjodia 



