PROFESSOR W. C. M‘INTOSH AND MR E. E. PRINCE ON 
2. Horizontal section through the branchial arches of the same form, April 20, 1886. The 
branchial arches are indicated by the figures (Roman): blr, basibranchial; injp, 
inferior pharyngeals ; bp, branchial papillee in section, : x 52 
3. Transverse vertical section through the abdominal region of fhe aapaneed isaval Anar- 
rhickas, the hind-gut being severed just in front of the urinary vesicle, June 20, 1886, . x 55 
4. Similar section behind the foregoing, the termination of the hind-gut and the urinary 
vesicle being cut, May 1, 1886: 7/, remains of longitudinal ligament, . : x 55 
5. Similar section through the urinary vesicle and anus (a more advanced stage), June 20, 
1886, . ; : x 97 
6. Section posterior to the anes awh the urinary vesicle ond its Nee ina postural 
form of the same date, . 5 x 97 
7. Section (transverse vertical) pas the etn st urinary roel in font of chee previous 
sections, May 1, 1886, : : 4 : : : 3 : x 55 
Prate XXVI. 
1. Intestine of the larval eas showing the circulation from the left side, February 
1886, . F : ; : x 40 
2. Similar view from the same sionan, seen hota the ay side, Febenaiy 20, 1886, é x 24 
3. Transverse vertical section through the kidney of the same form at an advanced stage, June 
20, 1886, : : x 230 
4, Transverse vertical eraon awe ihe Blpmerlne in the same species, Marchi lL; 
1886, . : : . Highly magnified 
5. Transverse section of the moroenerd| ofa enon of the first day, shone nuclei and noto- 
chordal investments, . : : 5 : ; : . Highly magnified 
Puate XXVII. 
1. Young Anarrhichas lupus reared in the St Andrews laboratory, May 14, 1886, : x about 12 
2. Circulation in the tail of the larval Anarrhichas, March 13, 1886, . ; . x 25 
3. Caudal region of the advanced larval Anarrhichas, showing the constrictions of fie noto- 
chord opposite the attachment of the neural and hemal arches, May 4, 1886, . 3 x 24 
4, Transverse section of the alimentary canal (stomachal region) of the advanced larval Anar- 
rhichas, June 20, 1886, : ; ; x 150 
5. Transverse section of the cesophageal region of the aibaeniers etal with the Rrierion end 
of the heart below, March 29, 1886, . : 4 : 5 x 150 
6. Transverse section of the same region of the canal, January 16, 1886, c : . x about 60 
Puate XXVIII. 
1. Aboral termination of notochord and caudal circulation’ in the larval salmon (Salmo salar), 
1 day old, 5 . Magnified 
2. Lateral view of the ereuiaaon in the region over the varitral fin in a aca Bion of the 
same age, a . Magnified 
3. Capillaries in the region of the fatty fin (of the fee of the same Sree) in course of 
development, . : . Magnified 
4. Ovum of the haddock (Gages caglesfinuia) 5th Boney the te Hastoriere are of ee 
Rize, «. x 60 
5. Ovum of the ling (Molva on gar is), 4th ey ay (eraleatons paseaee much ed neenle 
embryonic thickening very marked, : é : é : é : x 50* 
* This figure was drawn by Mr Prince. 
