280 APPENDIX 



2. Gcddes, P. Observations on the Resting State of Chlamydomyxa laby- 



rinthuloides, Archer. Ibid. xxii. (1882), p. 30. 



3. Hieronymus, G. Zur Kenntniss von Chlamydomyxa labyrinthuloides, 



Archer. Hedvvigia, Bd. xxxvii. (1898), p. 1. 



4. Jenkinson, J. W, Abstract and Review of the above paper by Hieronyimis. 



Quart. Journ. Micr. Sci. N.S. xlii. (1899), p. 89. 



5. Lankester, E. Ray. Chlamydomyxa monta'iia, n. sp., one of the Protozoa 



Gyranomyxa. Quart. Journ. Micr. Sci. xxxix. (1896), p. 233. 



6. Penard, E. Etude sur la Chlamydomyxa montana. Arch. f. Protistenkunde, 



Bd. iv. Heft 2 (1904), p. 296. 



LABYRINTHULA. 



The members of this genus consist of associations of nucleated proto- 

 plasmic units ("amoebae" of Zopf, "spindles" of Cienkowski) joined in 

 a network of sparingly branched and anastomosing threads. They are 

 met with in a diffuse or aggregated condition, and, as the result of 

 drying, the units pass into a condition of encystment, from which they 

 hatch out in the form of the amoeboid units. 



Two marine species were described in 1867 by Cienkowski (1), who 

 found them on algae growing on wooden piles in the harbour of Odessa : 

 L. vitellina, Cienk., in which the protoplasmic units contain a yellow or 

 orange colouring matter ; and L. macrocystis, Cienk., in which the units 

 are larger and colourless. Zopf (4) in 1892 described a freshwater 

 form very similar to L. macrocystis, parasitic on the alga Vaucheria. 

 He named it L. cienkowskii, Zopf. 



In the marine forms the system of connecting threads appears to have 

 a remarkably firm and rigid consistency, and Cienkowski describes the 

 movement of the units along the threads, as though the latter were 

 peculiarly differentiated structures ; but from Zopf's description of L. 

 cienkowskii it can hardly be doubted that they are pseudopodial in nature. 

 Zopf observed them to be slowly protruded from a mass of units, and to 

 be withdrawn, to move slowly from side to side, and to fuse with their 

 neighbours. He also describes the passage of food - granules along 

 them. 



The units are without a limiting membrane and contain a single 

 nucleus, with a nucleolus. When drawn out in the expanded condition 

 of the organism they are generally spindle-shaped (Fig. 3 (3)), but they 

 may present processes in three directions (Fig. 3 (4)). In the aggregated 

 condition the units are round or oval. Those of L. macrocystis measure 

 18-25 fj, in long diameter, those of L. vitellina and L. cienkowskii about 

 1 2 /*. The protoplasm is granular, and in L. vitellina contains a yellow 

 or orange fatty pigment, soluble in alcohol. A small vacuole is usually 

 present, but it is not stated that it is contractile. 



The whole organism, or a part of it, is often found in the aggregated 

 condition (Fig. 3 (5)), and the marine species may thus form masses 

 measuring a millimetre or so in diameter. The main aggregate is 

 described by Cienkowski as invested, in L. vitellina, by a " cortical sub- 

 stance" (neither protoplasmic nor of the nature of cellulose) through 



