J. M. Macfarlane. — Sarraceniaceae. 15 



the area. Such areas may therefore be viewed as temporary resting places for smaller 

 insects, that allow them time to overcome the fear excited through the impediment 

 offered by the hairs to their feet. 



In Darlingtonia the external epidermal surface is covered with alluring glands as 

 in Sarracenia. But each is one-celled on surface view, and four- to five-celled in 

 section (Fig. 5 Ea). The lowest cell of the series is largest and goblet-shaped. These 

 glands become greatly more abundant and complex round the involute edge of the 

 mouth, as shown in Fig. 5JB76, Ec. Each consists of 4 to 5 times the number of surface 

 cells, and these are surrounded by striated overhanging neighbor cells that are often 

 of a brilliant crimson color. The inner surface of the involute edge is smooth to the 

 depth of 5 — 6 mm and devoid of glands. Below this is a narrow band of long stiff 

 outstanding hairs, that are different from all others of the cavity. The inner surface 

 of the bilobed process in front of the mouth secretes honey copiously from many glands, 

 and amongst these glands are short strong hairs that are all directed upward toward 

 the mouth. The hood of the pitcher likewise functions with the bilobed process as an 

 attractive surface, and has many long strong downwardly directed hairs, intermixed 

 with glands that are 1 — 2-celled on surface view. The conducting surface has the 

 same structure and relation as in Sarracenia, and it gradually merges into the detentive 

 surface that bears long delicate hairs. 



Biological Relations of the Leaves (Blattbiologische Verhältnisse). The 

 striking biological peculiarities shown by the leaves of the Sarraceniaceae early attracted 

 the attention of botanists. Lobel in 1570, Glusius in 1601, and Johnson — in 

 Gerard's Herbai — in 1633, all refer to, and in some cases figure the leaves of S. 

 purpurea and S. flava, while plants were grown at South Lambeth, London, during 

 the last-named period by John Tradescant J r - who had brought them. from Virginia. 

 Good descriptions and illustrations are given by Plukenet of the two species above 

 named (Phytogr. 1691, t. 152, fig. 3; 376, fig s 5, 6). But Miller in 1739 (Gard. 

 Dict. 3 rd ed. II.) mentioned the presence of water in the tubes, only to suppose that 

 they were intended to quench the thirst of birds etc. during long droughts. Even 

 Catesby who must often have wandered amongst wide areas of them, could only 

 suppose that the pitchers served "as an asylum or secure retreat for numerous insects, 

 from frogs and other animals which feed on them". While W. Bartram and Robin 

 seem both to have interpreted their meaning correctly, Macbride first gave a very 

 careful account of the structure of the pitcher of S. minor, and its capacity for catch- 

 ing insects. Subsequent observers confirmed or denied this, tili Mellichamp established, 

 on a firm basis, the insectivorous character of the group, through painstaking observations 

 in the field on S. minor, and to a less degree on S. flava. Hook er extended these 

 studies to other forms in his address before the British Association in 1874. Many 

 subsequent observers have greatly amplified our knowledge of the group. 



In their native haunts these plants develop their pitchered leaves in April and 

 May along with the flowers (Fig. 10) or more commonly soon after the flowers have 

 blossomed. During May and June the alluring glands over their surfaces begin to 

 exude nectar drops, which are highly attractive to insects. In S. flava, and to a less 

 extent in S. Sledgei and S. Drummondii, with their rib-like longitudinal veins, the 

 surfaces of the veins may be thickly studded by large nectar drops, while in early 

 June the entire outer pitcher surface below the mouth may glisten with an almost 

 continuous secretion. Tempted upward by this over the exterior of the pitcher, or 

 alluring surface, they in some cases reach the orifice directly, or may first move up 

 to the lid in Heliamphora and Sarracenia, or to the bilobed Aap in Darlingtonia. The 

 secretion along the outer margin of the lid in Sarracenia — specially in S. flava and 

 S. Sledgei — or along the orifice in S. psittacina and Darlingtonia, is abundant and 

 sweet. They thus incline to step on to the inner surface of the lid, that forms the 

 attractive surface, or they may at once step inside the tube, on to the conducting 

 surface. When an insect has reached the latter it at once begins to show peculiar 



