A STUDY OF METAMERISM. 475 



Tig. 32, a b.— Ditto, 15th, 16th, and 17th. 



Fig. 33, a b. — With compound metamere 10 — \^. 



Fig. 34, a b. — Ditto 7 — |. Also category v. 



Fig. 35, a b c. — Ditto 9 — ^. Also category ii. 



Fig. 36, a b c. — Spiral vii, involving 11th, 12th, and 13th metameres. 



Fig. 37, a b c. — Compound metamere 12 — f|. 



Fig. 38, a b c. — Category ii. 



Fig. 39, a b c. — Compound metamere 15 — If. 



Fig. 40, a b. — Spiral vii, involving 8th, 9th, and 10th. Also another 

 modification. 



Fig. 41, a b c. — Four compound metameres i and spiral vii. 



Fig. 42, a b c. — Compound metamere 3 — f , followed by complicated spiral. 



Fig. 43, a b c. — Two spirals vii, and compound metamere ii. 



Fig. 44, a b. — Compound metamere 6 — f . Spiral vii. Compound meta- 

 mere 13 — f|. 



Fig. 45, a b c. — Intercalated half-raetamere 15. iii. Spiral involving 

 15th — 19th metameres. 



Fig. 46, a b c. — A much modified anterior end. See construction c. 



PLATE 42, 

 All figures of L. foetidus except Fig. 74 (L. terrestris). 



Fig. 47. — All of the abnormalities drawn from one very abnormal worm. 

 The numbers inserted between the spirals, compound metameres, &c., give 

 the number of normal rings that have been omitted. 



Figs. 48 — 50. — ^Vasa deferentia opening on different metameres. Tiie 

 figures as seen from below. 



Figs. 51, 52. — Vasa deferentia doubled on one side. Seen from below. 



Figs. 53 — 55. — Both vasa deferentia on 10th, 12th, and 14th metameres 

 respectively. Projections from above. 



Figs. 56 — 58. — Vasa deferentia on alternate segments. Diagram as seen 

 from above, so that right and left of Figs. 53—60 are reversed as compared 

 with Figs. 48—52 (below). 



Figs. 59, 60. — Vas deferens doubled on one side. Projections from above. 



Figs. 61 — 64. — Dissections of compound metameres to show arrangement 

 of septa, &c. 



Figs. 65—70. — Dissection of spirals to show condition of septa. 



Fig. 71. — Failure of surface line to meet above. Septa were normal. 



