MARINE PROTOZOA FROM WOODS HOLE. 
459 
close together and 1 at some distance, near the largest anal cirrus. The peristome, contractile vacuole, 
and nucleus are similar to the preceding. Length 36//; width 22//. 
Stein assigns only 7 ventral cirri to this species, but he also describes 2 very line bristle-like cilia 
(p. 125) and pictures them in tigs. 18, 19, 20, and 21 of his Taf. iii in the same relative position as my 
eighth cirrus. I am positive that cilia do not occur on the ventral face of this form, and that the 
characteristic cirri are the sole locomotor organs. 
Key to families of Peritrichida. 
a. Peristome drawn out into fumjel-like process; parasitic Family Spirochonidss 
b. Adoral zone and circlet of cilia at opposite end. Adoral zone left-wound. Parasitic (one genus, * Lichnophora) . 
Family Lichnophoridi e 
c. Adoral zone a left-wound spiral. Attached or unattached forms Family Vorticettidx 
Genus LICHNOPHORA Claparede '67. 
(Gruber ’84; Fabre-Domergue ’88; Biitschli ’88; Wallengren '94; Stevens 1901. ) 
Small or medium-sized colorless animals, extremely elastic and flexible. The anterior part, bear- 
ing the adoral zone, is round or oval in ventral view, and has a flat ventral and a highly arched dorsal 
surface. The posterior end of the animal is reduced to a stalk-like structure which is broadened at 
the extremity to form a sucking disk. The surface of this disk and the surface of the peristome may 
be brought into the same plane by the characteristic bending of the stalk portion. A ciliated girdle is 
placed at the edge of the sucking disk. A well-developed adoral zone incloses the peristome; it begins 
Fig. 57. — Aspidisca polystyla. 
Fig. 58. — Lichnophora macfarlandi. 
at the mouth on the left side and includes nearly all of the peristome in its left-wound spiral, the 
extremity approaching closely the end near the mouth. The macronucleus is a long-beaded structure, 
or it may be in several parts connected by strands (Gruber). The contractile vacuole is on the left 
side in the region of the mouth. Salt water. 
Lichnophora macfarlandi Stevens. Fig. 58. 
The body is elongate; oral disk variable in form, attachment disk clearly defined and constant. 
The stalk is very contractile and elastic, constantly changing in shape. When detached from the 
host the animal moves with a very irregular and indefinite motion. When attached it moves freely 
over the surface on its pedal disk. The latter is bordered by four membranes composed of cilia. A 
distinct axial fiber extends from the pedal disc to the peristome and gives off a number of branches. 
This fiber is analogous to the myonemes in Vorticella. An indistinct longitudinal furrow can be made 
out occcasionally. The nucleus is in 5 or 6 separate pieces, of which 1 is found in the pedal disk and 
1 or 2 in the neck. 
On the egg capsules of Orepidula plana; also reported upon annelids at Woods Hole. 
Length 60// from disk to extremity of the peristomial disk. 
This form does not agree in all respects with Stevens’s species, but the agreement is so close in 
other respects that I believe it can be safely identified as L. macfarlandi. The mode of life is different, 
and the macronucleus is different, there being from 25 to 30 fragments in Stevens’s form and only 5 or 
6 in the present one. There is, however, the same evidence of chain formation in both of them. The 
length of the oral cilia in Stevens’s form is 18// in fixed and 30// in living forms. In the Woods Hole 
form the cilia are not more than half that length. 
