97 



round sporangia, which in some cases even showed young outgrowths 

 in form of short ramifying tubes. 



2. Foraminifera. 



In an extensive collection of sections of Foraminifera which I owe 

 to the kindness of my friend Prof. Carpenter, there were many 

 genera which showed numerous filaments of fungi in their test itself, 

 viz. Polystomella, Orbitolina, Heterostegina, Amphistegina, Cal- 

 carina, Alveolina, and Operculina. The last genus shows best that 

 these parasitic tubes, which sometimes are very large, are quite 

 different from the two kinds of tubes rightly described by Carpenter 

 as belonging to the test itself. They generally run at right angles 

 to the finer. tubuli, and are easily distinguished from both kinds of 

 typical tubuli by their irregular course, and by their frequent branch- 

 ing, and even anastomosing. They are absent in many specimens 

 of the above-named genera, and could not be found in Cycloclypeus, 

 Nummulina, and Nonionina. 



3. Corals. 



All the genera of Corals which I investigated contained parasitical 

 fungi, viz. Astraa diffusa, Porites clavaria, Tubipora musica, 

 Corallium rubrum, Oculina diffusa, Oculina, sp., Alloporina mirabilis, 

 Madrepora cornuta, Lobalia prolifera, Millepora alcicornis, Fungia, 

 sp. The fungi were most frequent in the genera Tubipora, Astrcea, 

 Porites, and Oculina, the last three of which contained also many spo- 

 rangia, which in the red coral were very scarce and often wanting. 



4. Bivalves. 



I agree with Wedl that the tubuli described by Carpenter in the 

 shells of Bivalves are all parasites. Many of them agree in every 

 respect with those found in other hard structures of the Inver- 

 tebrata, of whose parasitical nature there can be no doubt ; and even 

 possess sporangia, as those of Thracia, Lima, Cleidothcerus, Anomia, 

 Ostrea, Meleagrina. With respect to those of the genera Litho- 

 domus, Area, Pectunculus, Nucula, Cardium, it is true that their 

 straight course and more regular distribution speak in favour of their 

 typical occurrence ; but as in some cases true parasites also are very 

 regularly distributed through the shells, there can be no doubt that 

 even these do not really belong to the structure of the shells. 



