MARINE PROTOZOA FROM WOODS HOLE. 
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Key to the, marine genera, of Tintinnidx. 
Diagnostic characters: Body attached by a stalk to a cup. Inside the zone of membranelles is a ring of cilia (par-oral). 
1. The test is gelatinous and more or less covered by foreign particles Genus Tintinnidium 
2. The test is ehitinous and clear. No foreign particles Genus Tintinnus 
3. The test is ehitinous; covered by foreign particles, growth rings frequent Genus *Tintinnopsis 
4. The test is ehitinous, often covered by foreign particles. The test is marked by discoid, circular, or hexagonal spots 
Genus CodoneUa 
5. The test is perforated by pores of circular or hexagonal form Genus Dictyocysta 
Genus TINTINNOPSIS Stein ’67. 
(Stein ’67: Kent '81; Daday '87; Biitschli ’88.) 
Medium-sized ciliates, inclosed in a ehitinous lorica with embedded sand crystals. The form of 
the house, or lorica, varies greatly. In some cases the mouth opening is wide, giving the lorica a bell 
form; it may be long and tubular, short and spherical, or variously indented. The animal is attached, 
as in the closely allied genus Tintinnus, by a peduncle to the bottom of the lorica. The anterior end 
of the animal is inclosed by two complete circles of cilia; one, the outer, forming the adoral zone, is 
composed of thick tentacle-like membranelles, the other consists of shorter cilia within the adoral 
zone. The mouth leads into a curved cesophagus containing rows 
of downward-directed cilia ( Daday ) . The entire body is covered 
with cilia, but as the lorica is always opaque these can be made 
out only when the animal is induced to leave the house. The 
only difference between this genus and Tintinnus is the covering 
of foreign bodies — usually sand crystals. Movement is rapid and 
restless, and peculiarly vibratory, owing to the apparent awkward- 
ness in moving the house. Salt water. 
Tintinnopsis beroidea Stein, var. plagiostoma Daday. Fig. 47. 
Synonym: CodoneUa beroidea Entz ’84. 
The shell is colorless, thimble-shaped, with a broadly rounded posterior end. The body is 
cylindrical. The internal organs were not observed. Membranelles 24 in number. 
Length 50 /<; greatest diameter 40//. 
Var. compressa Daday ’87. 
The posterior end of the shell is pointed, the lower third of the sheil is swollen, the upper 
third is uniform in diameter and without oral inflation or depression. Nucleus not seen. 
Length 70/4 ; greatest diameter 48//. 
Tintinnopsis davidoffi Daday. Fig. 48. 
The shell is large, elongated, and provided with a considerable spine. The chitin of the shell is 
covered with silicious particles of diverse size. The internal structures were not observed. 
Length of shell and spine 230/4 ; diameter of the oral aperture 54//. 
The variations of these species are considerable, and as the internal structures, such as the 
nucleus, are essential in fixing their systematic position, I place them as above, provisionally, and 
until further observations can be made. 
