NOTES AND MEMORANDA. 407 



Molluscoida. 



New Tunicata. — Professor Heller, in continuation of his previous 

 papers on the Tunicate fauna of the Adriatic and Mediterranean, now 

 describes * a number of new species from the Atlantic and Indian 

 Oceans, from the South Sea, and the Antilles ; these, of which there 

 are thirty, belong to the following genera: — Ascidia (6), Bhodo- 

 soma (1), Cynthia (6), Microcosmus (5), Pohjcarpa (8), Styela (3), and 

 Boltenin (1). He owes his opportunities to the kindness of Professors 

 Schmarda and Mobius, and to the director of the Museum Godetfroy 

 at Hamburg. 



He appears to have been especially struck by the extraordinary 

 similarity of the forms from these very ditferent regions ; not only 

 do all the species belong to known genera, representatives of which 

 are to be found in the European seas, but many of the species examined 

 were absolutely identical with such. Thus, Ciona intestinalis was 

 brought from Sydney, as was also the Styela grossa, which is not rare 

 at Trieste, while Cynthia dura, another Adriatic form, was collected in 

 the Antilles and oflf New Zealand. The Microcosmus claudicans, so 

 common in all European seas, was found in the whole extent of the 

 Indian Ocean and of the South Seas, while it does not appear to be 

 absent from the West Indian region ; and the same remark applies to 

 Pohjcarpa pomaria and P. varians. The paper is illustrated by six 

 plates of thii'ty-two figures. 



Arthropoda. 

 Gall-making Aphides. — The life-history and agamic multiplication 

 of the Aphididje have always excited the interest of entomologists, 

 and have even attracted the attention of some of the most eminent of 

 our naturalists. With all their vast numbers and their universality, 

 their life-history has, however, baffled the skill of many an observer, 

 and this has been especially the case in the gall-making forms which 

 so disfigure our trees. Kesearches carried on into the life of the 

 Phylloxera have, however, somewhat cleared the way, and Dr. Eiley 

 begins, vol. v. for 1879, of the ' Bulletin of the United States Geo- 

 logical Survey ' with some biological notes, in which he recounts the 

 following most remarkable history: It will be remembered that 

 destructive as these insects are, they are most fragile, and languish in 

 confinement, so to trace out all their daily history for a space of over ten 

 months was a labour requiring diligence and perseverance — one that 

 probably would not have been successful had not Dr. Riley been 

 helped by an enthusiastic lady friend. The first species studied is 

 known as Schizoneura americana. It infests the leaves of the American 

 elm, sometimes in such numbers as to cause all the leaves to fall. If 

 during the winter the cracks in the bark of an American elm that was 

 badly infested with this leaf-curling species the previous summer be 

 examined, there will pretty surely be found here and there a small 

 dull yellow coloured egg, about • 5 mm. long, probably still covered 

 with the remains of the female's body, quite dried up. Out from this 

 egg will in the early spring be hatched the little crawling creature 

 * ' SB. Akad. Wien.,' Ixxvii. (1878) 83. 



