65 



However, an authentic fragment which I have examined is in this respect quite different. Thus 

 in a median longitudinal section of a branch the longer cells of the medullary hypothallium are 

 27 — 50 u.., sometimes even up to about 60 u.. in Iength and 7 — 12, rather seldom up to 15, 

 but frequently about 10 u.. in breadth. The shorter cells of the said layer are 12 — 24, or up to 

 30, mostly 16 — 20 a. long. The perithallic layer exhibits cells which are squarish, 6 — 10 a. in 

 diameter, or vertically elongated and up to 18, occasionally even up to 24 [i. long. Besid^s, 

 as to the reproductive organs Heydrich states 1. c. : "Conceptakel 600 — 700 a., oberflachlich, 

 wenig erhabene Warzchen nur auf der Rückseite der Verzweigungen bildend". On the following 

 page, however, he states: "Conceptakel mit Tetrasporangien habe ich nicht gefunden. Die 

 Cystocarp-Conceptakel bilden ausserlich flache meist 1 mm. im Durchmesser fassende Erhaben- 

 heiten mit wenig erhabener Entleerungsöffnung. Die Höhle ist meist 300 ij., lang, 50 p.. hoch. 

 Carposporen oval". On the other hand, according to my own measurements they are but 

 400 — 500 u. in diameter when seen from the surface, subprominent and often not well defined. 

 In a median vertical section they are however of about the size last quoted, though now and 

 then somewhat larger. I will not at present express my opinion whether these organs are 

 cystocarpic, or hermaphroditic, or if the plant in fact is a Lithophyllum, which, however, seems 

 to be probable. I shall corae back to these questions on some future occasion, and for the 

 present leave them in abeyance, particularly because of lack of opportunity of examining a 

 sufficiënt large material. A few conceptacles examined were empty. 



In comparing the description of the structure of e. g. Lithophyllum Tamicnsc Heydr. 

 1. c. with that of L. moluccense Fosl. '), both afterwards identified by Heydrich himself, it will 

 be seen that his description here is almost as far from being in accordance with the fact as 

 his description as regards the species in question. This is in the main also the case as to 

 Archaeolithothamnion erythraetim (Sp. ptychoidcs Heydr.). Cp. Foslie. Melob. Arb. Heydr. p. 16. 

 The instances of incorrect description might be continued, but I suppose these instances to be 

 sufficiënt to support my identification of L. Bamleri on a small fragment rather than on the 

 description of the species 2 ). 



I have above subsumed Pcrispernuim hermaphroditum Heydr. under the species in 

 question. Of this plant too I have had the opportunity of examining an authentic fragment 3 ). 

 It fully resembles L. Bamleri in habit, with in part slightly thicker branches. As to the 

 structure of the former, Heydrich states 1. c. p. 411: „lm Langsschnitt tritt aber besonders 

 auffallend die facherförmige Stellung der Zellschichten hervor, die in regelmassig scharf abwech- 

 selnden Reihen den Thallus durchziehen. Die einzelnen Zeilen eines central orelegenen Fadens 



1) M. Foslie. Calcareous Algae from Funafuti — Det Kgl. Norske Vidensk. Selsk. Skrifter 1900, n° r, p. 10. 



2) "Nun enthalten leider die Diagnosen vieler Arten nur Angaben über den Habitus; in Folge dessen kommt es recht haufig 

 vor, dass eine sichere Bestimmung erschwert wird, oder dass man sich vor die Möglichkeit gestellt sieht, eine Pflanze mit demselben 

 Recht zu zwei oder drei Species zahlen zu könuen. Wollte man dann die fragliche Pflanze so ohne Weiteres einer dieser Species zutheilen, 

 so möchte dies der Botanik, als einer exacten Wissenschaft, wenig nutzen, und der Autor könnte nachher in die unangeDehme Lage 

 kommen, dass die nicht beschriebenen Merkmale solcher Species mit denen der von ihm hinzugerechneten Pflanze nicht im Einklang 

 stehen. Es ist daher jetzt unbedingt nothwendig, dass ein Autor, wenn er Prioritatsansprüche erheben will, die Diagnose nicht nur auf 

 den Habitus beschrankt, sondern sie auch auf Zeilen und Früchte ausdehnt". Heydrich in Ber. der Deutsch. Bot. Gesellsch. I90i,p. 418. — 

 I want to add that it is worse when an author cannot be relied on as to the description, or when he quotes incorrectly. 



3) I express my best thanks to Dr. Jean Chalon, who has shown me the favour to spare me a part of a specimen of this 

 species as well as a couple of other ones distributed by Heydrich himself. 



SIH0GA-EXPED1TIE LXI. 9 



