462 PROCEEDINGS OF SOCIETIES. 



by Captain Chimmo from the Sulu sea. The various structural 

 points of Sagitta were easily distinguished, and the striped mus- 

 cular fibre formed a high -power object of great beauty. 



A 'probaMy new Species of Sagitta exhibited. — Dr. Macalister 

 exhibited a specimen of Sagitta, obtained from the Godefroy 

 Museum in Hamburg, and supposed to have come from the 

 South Seas ; it was over 3 cm, in length with an elongated mar- 

 ginal fin ; no seminal vesicles or long surface bristles. The head 

 bristles were six on the left side and three on the right. The 

 jaws had three terminal spines and lateral saw-like teeth. The 

 nervous system exhibited only two lateral branches from the ven- 

 tral ganglion instead of the numerous little ramuli figured by 

 Professor Huxley. The specimen came nearest to S. Lyra, but 

 did not exhibit the caudal groove, and differed in the numbers of 

 denticles from that species as described by Krohn. 



On tlie Structure of the Leaf of Erythroxylon Coca, L. — Professor 

 McNab exhibited preparations of the leaf of the Coca plant, 

 Erythroxylon coca, L. The epidermis of the under side of the 

 leaf bears a number of very minute stomata. These stomata 

 measure about -x^o o" ^"^ length by yoVo" ^'^ diameter. The air- 

 spaces are themselves about -^^qq" to xoV o". ^-cross. The transverse 

 section of the leaf shows the epidermis of the upper side, then a 

 single row of palisade parenchyma, then the loose cellular tissue 

 (somewhat resembling the air-cells of the lung) with large inter- 

 cellular spaces, and lastly, the epidermis of the under side with 

 stomata. The midrib is strongly marked, and projects considerably, 

 thus contrasting with the thin laminae. Above the midrib, in the 

 middle line of the leaf, is a small longitudinal keel. On the inner 

 side of the leaf, on each side of the midrib, is a similar raised longi- 

 tudinal keel. These longitudinal keels have been mistaken by Sir 

 Robert Christison and other observers for lateral veins. A careful 

 examination showed that the keel consisted of epidermis and ground 

 tissue merely, no fibro-vascular bands running in it from base to 

 apex of the leaf. Baillon seems to be right in explaining the 

 formation of the keel as due to the mode of folding the leaves in 

 the bud. 



My X a strum-form, probably a new species, exhibited. Professor 

 E. Perceval Wright exhibited specimens of what he took to be a 

 species of Hiickel's genus Myxastrum. These approached some- 

 what to the only described species M. radians, found at the 

 Canary Islands, but still seemed in certain respects to difier there- 

 from. This form occurred not uufrequently in bottles in which 

 marine algae collected at Howth had been kept for some time in 

 a growing condition. The little dark-brown patches which clung 

 to the side of the glass next the light could be just seen with un- 

 assisted vision, and with them were associated Diatoms, Glwocapsa- 

 cells, and such like. The individual portions resembled minute 

 Actinophryans ; at certain times the "fluff}^ " nature of the pseu- 

 dopodia seemed to pass over into a more or less regular series of 

 rays ; at other times the ray-like portions were lost and the form 



