190 



produced bv pr.rasites. They are the most richly differentiated 

 of all known abnorrml tissue formations. Therefore we will 

 take them up at the end of our considerntion. 



The galls to b)e treated of in the present section ere al- 

 most exclusively Zoocecidia. Of the nniraals producing galls, 

 only the arthropods come uiider cqjisideration here, since the 

 galls produced by worms (nematodes) always have c: kataplastlo 



V ^ ,?52, ®*^^?!; of the animals which produce galls brings us 

 but little information of importance for consideration, since 

 we .'^rc concerned only with the diseased products of plant or- 

 gans, It will become clear thr.t the aysteniatic position of 

 vtt^ gall nniraal in one or another group of the arthropcfl s can 

 determine no regular connection botr^een the foin and structure 

 of the galls produced by then. 



^^® liii^ll* mentioned as producers of different kinds 

 of kataplasinas must be considered also under prosoplr.smaB. 

 Their products are very simple in form, as in structure. 



The diptera produce verir many prosoplasmr.g, the form 

 and structure of the galls being very different and often 

 very complicated, 



^■^^ hemiptera also produce numerous, usually yer"^ 

 simple prbsoplasmas, 



^^^ h|menopte ra produce alraost entirely proaoplasmas^ 

 those produced by the gall wasps (Cynipida) are especially 

 striking because of their si^^e, the diversity and complex- 

 ity of their forms and the difference in their internal " 

 structures. In describing the histology of prosoplasinas, 

 we will have to exajBine especially thoroughljr the struc- 

 tures occurring in Diptera and Cynipida galls. 



Of the Ooleoptera and Iiapidoptera . only a few proso- 

 pla3imxtic gnlls are known; thejr structure is relatively 

 simple , 



Among the Myoocecidia . there ape various galls v/hich re- 

 semble proBopla^mas in the regular arrangement of certain ele- 

 ments, for instance, of the calls of the menbrane tissue which 

 contain anthocyanin. Their cell forms , however, are no other 

 than thpse which v;e are accustomed to meet v/ith in arrested de- 

 velopments and in callus tissues. An especial position is t aken 

 by the gall/ produced on Polygonum chinense by Ustilago TreubljL' '-. , 

 This ma^ perhape be included iimong tlae prosoplasnas on account 

 of its peculiar fibres which are ^ike capillitia. 



At least we mt-y think thnt the transition from kata- 

 plasmas to prosoplusraas i* furnished by the nail of Ustil - 

 ago Treubii . According to Soaims-Laubach, this fungus, 

 like so many others, causes the production of canker-like 

 excrescences here and there on polygonum stons. The ex-' 

 crescenoes consist of spongy, parenchymatous wood-tissue, 

 on v/hich account, this sane fungus was referred to earlier 

 (p, 196), ThePe sprout out from the canker swellings v/hich 

 oorresxwnd entirely to the above described kataplasraas, 

 "fleshy, succulent, easily breakable excrescences", "the • • 

 irregularly bent, cylindrical and often longitudinally 



■^"•'i''''"""-'^------ --- ------------- 



Solma-Laubaoh in Ann, Jard, Botan. Buitenzorg, 1887, 



Vol. VX, p. 79. 



