400 ANATOMY OF SYEINGOLAIMUS 



than one occasion to occur every second or so when the live nema was placed 

 under the microscope under slight pressure (Fig. 1). The cross-section of the 

 pharynx is round-triquetrous, almost circular, with faint subordinate mark- 

 ings in the middle of each side, indicating on the whole a hexagonal structure. 

 There are no eyespots. The base of the pharynx may be surrounded by a 

 very faint ellipsoidal swelling. There is only a faint pharyngeal muscular 

 swelling, though there are fairly well developed mandibular muscles, lying 

 along the outside of the pharynx (Fig. 1, msc mnd). There is a rather distinct 

 but small conoid cardia, one-third as wide as the base of the neck, or less. 

 The ventriculus stains differently from the remainder of the intestine, showing 

 a distinct function to be discharged here ; in the li ving condition however the 

 ventriculus appears somewhat "structureless" (vntrc). The granules in the 

 cells of the intestine are of several distinct kinds: some of them are colorless 

 (grn trnsp int), others are emerald-green (grn vrd int) hence the specific 

 name smarigdus; none are birefringent. The content of the intestine is 

 usually reddish or greenish, and often is derived specifically from an alga be- 

 longing to the family Half siae (Fig. 3) , among which specimens of Syringolaimus 

 smarigdus are often found. There is no prerectum. From the somewhat 

 elevated lips of the anus, of which the anterior lip is the more elevated, 

 the cutinized rectum extends inward and forward a distance about equal to 



Fig. 2. Snails, natural size, covered with a very dark green "pile" or "felt" consist- 

 ing of microscopic algae. The nature of this growth is illustrated in Fig. 3. 



two-thirds of the corresponding body diameter. The lateral chords enlarge 

 from one-fifth (terminad) to one-half (mediad) as wide as the body. From 

 the medium-sized continuous vulva, the cutinized vagina leads inward at 

 right angles to the ventral surface three-fifths the way across the body. The 

 uteri contain only one egg at a time, are straight, three to four times as 

 long as the body is wide, and from one-fourth to one-sixth as wide as long. 

 The two opposite, equal, symmetrically arranged ovaries, about half as wide 

 as the body, are reflexed about two-thirds the distance back to the vulva and 

 contain ten to fifteen ova, mostly in single file. The elongate egg may be 

 3 to 4 body-widths long, appears relatively narrow, and seems to be deposited 

 before segmentation. 



;| }f ^ 4 - 7r ^.3' ' ' JjJ^-XJ.eswm The single gubernaculum (gub} 



may consist of two arcuate, subslender, parallel, amalgamated pieces, and is 

 rather closely applied to the spicula. Phasmids(?) (Fig. 1) occur on the 



Fig. 1 .Male of Syringolaimus smarigdus, together with four different views of the 

 head end. Below, a diagrammatic drawing of the front view of the head. Above, three 

 sketches showing different attitudes of the "mandibles" or fossores. The fossores are 

 also shown in both the other illustrations. The lettering of the illustrations consists 

 of self-explanatory abbreviations arranged in the Latin order; grn vrd int granulum 

 viride intestinalis, green granule of the intestine; etc. 



