eyes small
Macrostomum ruebushi var shenandoahensis Fig 27-30.jpg
Macrostomum ruebushi var granulophorum Fig 19-23.jpg
This stilette is lined by bands of muscles which presumably aid in ejaculation. The stilette has a bend of almost a right angle at its sharpened termination and opening. p. 36
Macrostomum riedeli Fig 1-7.jpg
The penis -stilette is funnel- shaped with an obliquely truncated base. (Distal?) opening is oval in shape and terminally truncated. p. 291
Macrostomum ruebushi var recurvostylum Fig 24-26.jpg
The eyes are small, black, and are not embedded in the brain tissue. The penis-stilette is an irregularly reduced funnel with a pointed end hooked into a right hand bend. The opening is terminal and is toward the posterior. The base is wide and crenated. p. 39
Macrostomum ruebushi var crenatostylum Fig 11.jpg
The long oval opening occupies the entire end of the bent portion of the stilette. The base is crenated. The hooked end of the stilette points ventrally toward the male opening. p. 29
Macrostomum ruebushi Fig 8.jpg
The penis-stilette is a greatly curved funnel which extends from a very broad, deeply indented base and suffers two changes of direction-one a half circle and the other a right angle bend at which point by a gradual reduction the genital canal terminates in a very sharp point. The external opening is terminal and oval in shape and is formed by an angular truncation of that part of the stilette. The sperm-cells possess a tactile feeler, an undulating midbody provided with two short setae, and a highly vibratile tail region. The setae appear early. A longitudinal row of chromatin granules extends from the origin of the lateroposterior pair of setae. p. 24
Macrostomum tennesseensis Fig 7-10.jpg
Macrostomum ontarioense Fig 1-5.jpg
sperm-cell composed of feeler, middle part with chromatin granules and two setae and 'tail' region. p. 134