摘要:

SUMMARYIn the foregoing paper an account of the morphology and development ofObelidium mucronatum, a seemingly rare chytrid inhabiting the submerged exuviae of midges and caddisflies in the vicinity of Ann Arbor, Michigan, is given. The zoöspore after becoming quiescent and retracting its cilium produces an acumination which will form the apical spine of the mature sporangium. Coincident with this or generally later, the rudiments of the rhizoidal system are produced from the opposite part of the spore body. Subsequently, an apophysis is formed by the inflation of the primary germ tube and portions of the primary branches. The sporangium develops from the expanded body of the original spore and at maturity consists of three parts, the solid apical spine, the narrowly to broadly ovate mid-region which contains the bulk of the protoplasm carried into it from the rhizoids, and a lowermost, cup-like, distinctly thick-walled region which may be prolonged into a funnel- or stalk-like structure. The mature sporangium is separated from the profusely branched and extensive rhizoidal system by a septum laid down between the base of the sporangium and the sub-sporangial apophysis. The posteriorly uniciliate zoöspores are delimited within the sporangium, emergeen massethrough a sub-apical pore, and after their discharge rest for a time at the orifice before undergoing a period of preparatory swarming which terminates with their dispersal. Sometimes, instead of aRhizidium-likemethod of development,O. mucronatummay exhibit aChytridiumhabit of growth, a part of the thallus being extramatrical and the remainder intramatrical. No resting spores have been found. Similarity in body structure and method of development ofObelidium, Rhizoclosmatium, Siphonaria, andAsterophlyctis, all exuviae-inhabiting forms, suggests that they are closely related genera.

ISSN:0027-5514    

DOI:10.1080/00275514.1938.12017246

出版商:Taylor&Francis    

年代:1938

数据来源: Taylor

摘要:

SUMMARYA hitherto undescribed species ofPhomopsiscausing a definite canker and gall disease on Gardenias (Gardenia jasminoidesEllis) is herein described asPhomopsis Gardeniae.This pathogene is apparently confined to a single host species but with a rather wide geographical distribution.

ISSN:0027-5514    

DOI:10.1080/00275514.1938.12017247

出版商:Taylor&Francis    

年代:1938

数据来源: Taylor

ISSN:0027-5514    

DOI:10.1080/00275514.1938.12017248

出版商:Taylor&Francis    

年代:1938

数据来源: Taylor

ISSN:0027-5514    

DOI:10.1080/00275514.1938.12017249

出版商:Taylor&Francis    

年代:1938

数据来源: Taylor

ISSN:0027-5514    

DOI:10.1080/00275514.1938.12017250

出版商:Taylor&Francis    

年代:1938

数据来源: Taylor

摘要:

SUMMARYTwo conidial fungi,Cercospora platanifoliaandStigmina Platani, occur together on the foliage of sycamore. They cause a leaf blight disease that occasions severe defoliation.During autumn spermogonia and perithecial primordia are initiated concurrently on the fallen leaves.After about two months spermatia cease to be formed and by the following spring the perithecial stages are mature. The perfect stage ofCercospora platanifoliaisMycosphaerella platanifoliaCooke; that ofStigmina Platanihas not previously been described and is herein given the nameMycosphaerella Stigmina-Platani.

ISSN:0027-5514    

DOI:10.1080/00275514.1938.12017251

出版商:Taylor&Francis    

年代:1938

数据来源: Taylor

摘要:

SUMMARY1.The results of a general cultural investigation with species of the Thelephoraceae and related fungi are presented in tables I-III.2.InCytidia solicina, (Fries) Burt the heterothallism is of the tetrapolar type, both the barrage reaction, described by Vandendries and Brodie (1933), and the false clamp connection reaction, described by Quintanilha (1935), occur on the community of the“B”factor.3.InPeniophora ludovicianaBurt the heterothallism is of the bipolar type. The cells of the haploid hyphae are always multinucleate. The cells of the diploid hyphae are initially multinucleate but finally binucleate clamp bearing cells develop. In this species both the haploid and the diploid mycelia produce basidiospore fructifications in culture. The young haploid basidia are binucleate and a fusion of nuclei occurs. The occurrence of a fusion nucleus in the haploid phase provides additional evidence of the origin of homothallic species from heterothallic ancestors.4.InPeniophora gigantea(Fries) Massee,Coniophora cerebella Pers.and an unidentified species ofCorticium, no.526, the cells of the mycelium of polysporous cultures are multinucleate. Abnormal clamp connections are produced in connection with cell division in the multinucleate cells.

ISSN:0027-5514    

DOI:10.1080/00275514.1938.12017252

出版商:Taylor&Francis    

年代:1938

数据来源: Taylor

ISSN:0027-5514    

DOI:10.1080/00275514.1938.12017253

出版商:Taylor&Francis    

年代:1938

数据来源: Taylor

ISSN:0027-5514    

DOI:10.1080/00275514.1938.12017254

出版商:Taylor&Francis    

年代:1938

数据来源: Taylor

ISSN:0027-5514    

DOI:10.1080/00275514.1938.12017255

出版商:Taylor&Francis    

年代:1938

数据来源: Taylor